In a large bowl add the 80% melted butter, sugar, and brown sugar. Whisk together until smooth. Add in 1 whole egg and 1 egg yolk (reserve the whites for a separate recipe or discard), vanilla extract, and almond extract. Whisk until just combined and smooth.
In another bowl, stir together the flour, salt, and baking soda.
Preheat the oven to 325 degrees F. (If you have a convection oven, do 325 degrees F at convection bake). In a small bowl stir together the white sugar and coarse white sugar crystals (optional but makes for a delicious cookie!).
Remove the dough and roll tall balls of dough (see the 2nd photo in the post). If you have a kitchen scale, the balls of dough should be about 1.7 ounces. Roll the balls of dough generously into the coarse white sugar crystal mixture. Place the balls of dough in the freezer for 5-10 minutes to firm up again (keeps them from spreading too much; you want the dough going into the oven as cold as possible.)
Place dough balls on a parchment or silpat lined sheet pan and bake for 9-11 minutes. Watch carefully being sure to not over-bake. Slightly under-baked sugar cookies are the BEST! Remove and let stand on cookie sheet for 2 minutes before removing to a cooling rack.
Meanwhile prepare the frosting. In a large bowl, beat together the room temperature butter and cream cheese until completely smooth. Add in the vanilla and salt. Beat to combine. Add in the powdered sugar and then beat until the frosting is smooth (it will seem like you need more liquid, but just keep beating, it will come together!)
Frost each cooled cookie with frosting and add with your favorite sprinkles. Enjoy! Store any leftover cookies in an airtight container in the fridge.
Total time does not include mandatory chilling time.