Preheat oven to 350°F. Generously grease two 6-cavity donut pans. Set aside
In a medium mixing bowl, whisk together the flour, sugar, baking powder, salt and baking soda. With a pastry blender, cut the butter into the flour mixture until it resembles coarse crumbs.
In a separate medium mixing bowl, beat the eggs, sour cream, and vanilla until well combined. Pour the egg mixture into the flour mixture; mix well.
Carefully place batter in a big zip-top bag. Seal the bag with as little air as possible. Cut one corner of the bag and pipe batter into the pans, filling each hole two-thirds full.
Bake for 9-11 minutes. Allow the donuts to cool in the pan for 5 minutes, then carefully transfer them to a cooling rack to cool completely.
Puree the strawberries in the bowl of a food processor. Add the powdered sugar and blend until combined.
Transfer the glaze to a shallow bowl. Dip the cooled donuts' tops in the glaze and lay them on the cooling rack glaze-side up or use a pastry brush to glaze them.
Allow the glaze to set before serving.