Gather and prep all of your ingredients. Pre-heat oven to 325F.
In a bowl, beat together the allulose and butter using a hand-mixer. Once fluffy, beat in the egg, egg yolk, and vanilla extract.
Add in the almond flour, baking powder, and salt. Beat again until just combined and all almond flour is incorporated into the batter.
Spread the batter into a prepared baking pan and bake for 20-25 minutes or until the center is puffed and edges golden brown. The texture should still be quite soft.
Prepare the frosting by beating the butter and cream cheese together until smooth. Add in the allulose and vanilla, then beat again until well combined.
Optionally add in sugar-free sprinkles of choice.
Once the bars have cooled, spread the frosting over the top and refrigerate for 30-45 minutes to set.
Remove the bars from the baking pan and cut into slices. Store in a covered container on the counter for up to 5 days or in the refrigerator for up to 10 days. Enjoy!