Preheat the oven to 400 degrees F. Line a rimmed baking sheet with parchment paper.
Sift the almond flour, baking powder, paprika, onion powder and salt into a large microwave-safe bowl. Add the mozzarella and cream cheese and use your fingers to evenly distribute the cheeses. Microwave on high for 1 minute. Knead the mixture with your hands or stir with a rubber spatula briefly. Microwave again until the cheeses are melted and the dough looks smooth, 15 to 30 seconds more. Let stand until cool enough to handle, just a few minutes.
Add all but 1 teaspoon of the egg to the dough and knead with your hands to incorporate. Sprinkle the dough with extra almond flour if it looks too sticky.
Divide the dough into 4 equal pieces. Moisten your hands and form each piece into a slightly domed patty about 3 1/2 inches in diameter. Arrange on the prepared baking sheet, brush the tops lightly with the remaining egg and sprinkle with the sesame seeds.
Bake until light golden brown all over, 12 to 16 minutes. Let cool on the baking sheet for 10 minutes, then carefully slice through the middles with a serrated knife.