In a large bowl, sift together flour, baking soda, baking powder.
In a separate small bowl, beat egg whites until they reach soft peaks.
In another bowl, whisk together buttermilk, orange juice, egg yolks, melted butter, orange zest, and both extracts. Add in the champagne and stir to combine.
Slowly add buttermilk mixture to flour mixture, stirring with a wooden spoon or rubber spatula to combine. DO NOT overmix. There may be flour clump in the batter, but that is okay.
Now, fold in the egg white, only folding a few times until barely combined. You do not want to deflate the egg whites.
Heat a buttered griddle or skillet over medium low heat. Scoop batter into the pan with an ice cream scoop or ¼ cup measure.
Cook until the top of the pancakes look dry, and bubbles emerge, about 2 minutes. Flip and cook an additional 30 seconds-1 minute.
Mimosa Glaze
In a large bowl, whisk together all of the ingredients until smooth.
If the mixture is too runny, add more powdered sugar, one heaping tablespoon at a time. If it is too thick, add in 1 tsp of orange juice at at time until the desired consistency is reached.
Pour immediately over warm pancakes and serve.
Notes
Pancakes will keep in an airtight container in the fridge for up to 3 days. They can be placed in the freezer for up to one month.