First, whisk together eggs, milk, melted & cooled butter, vanilla and almond extracts in a medium bowl until combined. Then, in a large bowl, whisk together the flour, collagen (if using), sugar, baking powder and salt. Pour wet ingredients into dry ingredients and switch to a spatula to stir until just combined. It's okay if there are clumps! Allow batter to rest for ~15 minutes, while you prepare the frangipane filling and heat up the pan.
2 large eggs, 1 ½ cups milk of choice, ¼ cup unsalted butter, 1 tsp vanilla extract, 1 tsp almond extract, 2 cups gluten free 1-to-1 flour, ¼ cup unflavored collagen peptides, 3 tbsp cane sugar, 4 tsp baking powder, pinch of kosher salt
In a large bowl or the bowl of a stand mixer, add the butter and sugar. Beat until combined (about 1 minute). Then, add in egg and almond extract and beat again. Finally, add in the almond flour and salt, and beat again until combined. Transfer frangipane to a piping bag or a ziplock bag with one of the corners cut off.
¼ cup unsalted butter, ¼ cup cane sugar, 1 large egg, 1 tsp almond extract, ¾ cup + 2 tbsp almond flour, pinch of kosher salt
Bring a griddle pan to medium-low heat or an electric griddle to about 350F. Once thoroughly pre-heated, grease with butter. Then, scoop out ¼ cup of batter per pancake. Add the frangipane swirl starting at the middle of the pancake and going out the edge, pushingly slightly into the batter so it's not raised off the pancake too much. You may have extra frangipane filling.
Allow the pancakes to cook for about 3-4 minutes, or until bubbles appear on the surface and the bottom is golden. Then flip and continue cooking for about 3 more minutes, or until golden. Optionally, top with powdered sugar and/or maple syrup. Enjoy!