Coconut Key Lime Donuts- Easy Yeast Donuts

These donuts can be made ahead and proofed overnight! Add any toppings or fillings you like, but I recommend trying these for a tropical twist! Recipe below.

Dough:
5 cups flour
1 1/2 cups lukewarm milk
1/4 cup warm water
2 teaspoons salt
1 cup granulated sugar, plus one tablespoon
2 teaspoons yeast
6 tablespoons shortening
2 lightly beaten eggs

Lime Curd:
2 lightly beaten eggs
1/4 cup freshly squeezed key lime juice
1/4 cup granulated sugar
6 tablespoons butter

Toppings:
2 cups powdered sugar
2-4 tablespoons milk
Vanilla extract (optional)
Sweetened coconut flakes
Zest of two limes