The three of us often have been in the position of making a recipe that uses only part of an egg. We've been in both situations: either having way too many egg whites to deal with or an abundance of yolks. Here are some recipes most of which we've used and recommend -- just in case you find yourself in a similar predicament! (We plan to add to these lists, too, as we discover more recipes.)
This post, we'll tackle the whites. Stay tuned for a post on yolks!
Fridge: 2-4 days, in an airtight container. But honestly, we've sometimes pushed it longer. You simply want to be wary once they get cloudy. BUT, why even bother when whites freeze amazingly?
Freezer: 12 months. Tip: Use an ice cube tray and put one egg white per space. Once frozen, move to a bigger container. Or, freeze in bulk and once defrosted, measure them out: one large egg white = 30 grams = 2 tbs.
One egg white:
Spicy Candied Nuts or Sugar & Spice Candied Nuts
Added to the wet ingredients in Maria's Granola Recipe (Will make more clumps & crunch.)
Dutch Baby (Plus 2 whole eggs)
Use as a wash for basically any type of bread, pie, or pastry like dough (such as Potato Knish) to gain an attractive sheen and better browning.
Cheddar Cheese Twists
Italian Buttercream Frosting
Egg White & Kale Frittata
Swiss Meringue Buttercream (Sarah's Favorite recipe! Uses 1, 4, or 12 whites, depending on the size of your cake.)
Fudgy Chocolate Walnut Cookies
Chocolate Espresso Buttercream (Omit espresso powder for plain, delicious chocolate.)
And even more:
Flourless Almond Raspberry Cake (6-8)
Chocolate Souffles (8)
Almond Raspberry Layer Cake (10)
Marbled Angel Food Cake (11-12)
Angel Food Cake (11-12) or this recipe (12)
Chiffon Cake (13 plus 2 whole eggs. Check out her other chiffon cakes. They are all amazing.)
Chocolate Angel Food Cake (15)