Muffins:
1 cup whole wheat pastry flour
1/2 cup all-purpose flour
1 1/2 teaspoons baking powder
1/4 teaspoon salt
1/3 cup granulated sugar
1 cup milk (any kind will work)
1/4 cup freshly squeeze orange juice
1 large egg
2 teaspoons vanilla extract
1/2 stick unsalted butter, melted
zest of two oranges
3/4 cup milk chocolate chips, tossed in a bit of flour

crunchy topping:
3/4 cup brown sugar
1/2 teaspoon cinnamon
1 tablespoon flour
2 tablespoons softened butter