frozen blueberries
will add even more time to
a pretty long bake

source, 2 loaves
1 stick soft butter, 3/4 c sugar, 1 t lemon peel, 1 c full fat plain greek yogurt, 2 eggs, 2 t powder, 1/2 t soda, 1 t salt, 2 c flour, 2 1/4 c blueberries
mix, pour into parchment-lined loaf pans, sprinkle with more sugar, 350 F, 75 minutes