The FLUFFIEST baked donuts, filled with pieces of summer cherries, and dipped in a pink cherry glaze, these donuts are the perfect fast and easy treat that will please any crowd! The secret ingredient that makes these donuts so fluffy? Kefir! If you guys  aren’t using kefir in your baking yet, you definitely should be. Kefir is a tangy, cultured “milk smoothie” that’s packed with protein, calcium, and Vitamin D! it gives such a great texture to baked goods too! So with Cherry season in peak bloom, this is the time to make these easy baked donuts that everyone will…