Silky cinnamon vanilla custard meets a thin almond crust in this Sugar-Free Cinnamon Vanilla Custard Pie. Each chilled slice has a dense, smooth center, a lightly spiced finish, and a modest yogurt rosette on top. It looks like a classic bakery pie, yet each serving has about 3g net carbs and 11g protein.
The recipe takes a little patience because the pie needs time to cool and chill. Most of the work is straightforward: press the crust, blend the custard without adding too much air, and bake until the center still has a gentle wobble. The refrigerator finishes the set and gives you clean slices.
Why You Will Love This Custard Pie
- Creamy without being heavy: Thick 0% Greek yogurt and reduced-fat cream cheese create a smooth filling with only a small amount of butter in the crust.
- Warm cinnamon-vanilla flavor: Cinnamon adds gentle warmth while alcohol-free vanilla rounds out the custard.
- A tender, thin crust: Almond flour, oat fiber, yogurt, and xanthan gum form a base that supports the filling without taking over the slice.
- Make-ahead friendly: The pie needs at least two hours in the refrigerator after cooling, making it practical to prepare earlier in the day.
- About 3g net carbs per slice: One pie makes ten servings with approximately 105 calories each.
If you enjoy smooth chilled pies, try the Sugar-Free Crème Brûlée Custard Pie next. For a spiced cream filling with a different texture, see my Sugar-Free Gingerbread Cream Pie.
Ingredient Notes
For the tender crust
Finely ground almond flour gives the crust a soft, nutty crumb. Use almond flour rather than coarse almond meal so the thin shell holds together more evenly.
Oat fiber absorbs moisture without adding the starch found in oat flour. The two ingredients behave differently and should not be swapped in this recipe.
Xanthan gum helps bind the small amount of crust mixture. Measure carefully; too much can make the base rubbery.
Greek yogurt and egg white provide moisture and structure while keeping the crust tender. Add them after the dry ingredients are evenly mixed.
For the cinnamon-vanilla custard
Thick plain 0% Greek yogurt forms most of the filling. If liquid has collected on top of the yogurt, pour it off before weighing.
Reduced-fat cream cheese should be fully softened. Beating it with the allulose first helps prevent small lumps in the finished custard.
Whey isolate adds structure and protein. Choose an unflavored variety without added sugar.
One whole egg and three egg whites set the custard. Mix them in only until combined so the filling stays dense rather than airy.
Allulose sweetens both the crust and filling. The FDA explains how allulose is declared on nutrition labels.
You can also make your own condensed milk from allulose and cream with our Sugar-Free Keto Condensed Milk.
For the cream finish
The topping uses very thick Greek yogurt, a little whey isolate, and powdered allulose. Chill the mixture before piping. One modest rosette per slice gives a finished look without overwhelming the custard.
How to Make Sugar-Free Cinnamon-Vanilla Custard Pie
1. Prepare the thin crust
Heat the oven to 325°F and lightly grease a 9-inch glass pie dish. Mix the almond flour, oat fiber, allulose, xanthan gum, and salt. Stir in the melted butter, egg white, and Greek yogurt until the mixture holds together.
Press the dough firmly across the bottom and up the sides of the dish, shaping a slightly raised rustic rim. Keep the base thin and even. Chill it for 10 minutes, then bake for 9 to 10 minutes. The crust should look set but not deeply browned.
2. Blend the custard gently
Beat the softened cream cheese and 70g allulose until completely smooth. Mix in the Greek yogurt, whey isolate, vanilla, cinnamon, and salt. Scrape the bowl well so no pockets of cream cheese remain.
Add the whole egg and egg whites. Mix on low speed just until the custard looks uniform. Avoid whipping extra air into the mixture because bubbles can disturb the smooth surface while the pie bakes.
3. Bake until gently set
Pour the custard into the warm crust and smooth the top. Bake for 38 to 44 minutes. The outer area should look set, while the center should move with one gentle wobble when the dish is nudged.
Do not wait for the middle to become completely firm in the oven. Residual heat and chilling will finish the set.
4. Cool and chill
Place the pie on a rack and let it cool for one hour. Transfer it to the refrigerator and chill for at least two more hours. A fully chilled custard cuts more cleanly and develops a denser, creamier texture.
5. Add the cream finish
Mix the very thick Greek yogurt, whey isolate, and powdered allulose until smooth. Chill for 15 minutes, then pipe one modest rosette on each slice. Dust the pie lightly with cinnamon just before serving.
Tips for Smooth Custard and Clean Slices
- Soften the cream cheese fully before mixing.
- Keep the crust thin and press it firmly into the glass dish.
- Mix the eggs on low speed and stop as soon as the filling is uniform.
- Remove the pie while the center still has a gentle wobble.
- Let it cool gradually before moving it to the refrigerator.
- Use very thick yogurt for the piped rosettes.
- Wipe the knife between slices for the cleanest presentation.
Storage
Cover the chilled pie and refrigerate it for up to four days. For the neatest finish, pipe the yogurt rosettes shortly before serving or store them separately. Freezing is not recommended because thawed yogurt custard can release moisture and lose its smooth texture.
Frequently Asked Questions
Can I use oat flour instead of oat fiber?
No. Oat flour contains starch and absorbs liquid differently. Use oat fiber to keep the crust proportions and nutrition profile consistent.
Why is the center still wobbly when the pie leaves the oven?
A gentle wobble prevents overbaking. The custard continues to set as it cools and becomes firm enough to slice after refrigeration.
Can I use regular vanilla extract?
The recipe specifies alcohol-free vanilla flavor. A different vanilla product may change the flavor slightly, so use the listed ingredient for the intended result.
Why should I avoid overmixing the eggs?
Overmixing can trap excess air in the filling. Gentle mixing helps the baked custard stay smooth and dense.
How long should the pie chill before slicing?
Cool it for one hour at room temperature, then refrigerate it for at least two hours. Longer chilling is fine and often makes slicing easier.
Sugar-Free Cinnamon-Vanilla Creamy Custard Pie Recipe
Sugar-Free Cinnamon-Vanilla Creamy Custard Pie
Ingredients
Equipment
Method
- Heat the oven to 325°F. Mix the almond flour, oat fiber, allulose, xanthan gum, and salt; then add the melted butter, egg white, and Greek yogurt.
- Press the dough thinly into a 9-inch glass pie dish with a raised rustic rim. Chill for 10 minutes, then bake for 9–10 minutes.
- Beat the cream cheese and allulose until smooth. Mix in the Greek yogurt, whey isolate, alcohol-free vanilla, cinnamon, and salt.
- Add the whole egg and egg whites just until combined. Pour the custard into the warm crust.
- Bake for 38–44 minutes, until the edges are set and the center still has a gentle wobble.
- Cool for 1 hour, then chill for 2 hours.
- Mix the cream-finish ingredients except the cinnamon. Chill for 15 minutes, then pipe one modest rosette onto each slice.
- Dust the pie lightly with cinnamon before serving.