Preheat oven to 350. Line 8 standard muffin tins with paper liners
Make Crumb Topping
Combine in a bowl flour, sugars and coconut
Add cold butter and mix with a fork or fingers just to form a crumble mixture, set aside
Make Muffins
Whisk in a bowl, flour, baking soda and salt
In another large bowl beat butter and sugar until light and fluffy
Beat in egg, then lemon zest, lemon juice and vanilla
Add in flour mixture and just combine
Fold in sour cream and coconut until fully mixed
Divide batter evenly between muffin tins
Add crumb topping evenly among muffin batter tops
Bake 15 to 20 minutes, until a toothpick comes out just clean. Cool in tins 5 to10 minutes then remive to wire rack to cool completely
Glaze Muffins
In a bowl whisk. Together confectioner's sugar and lemon juice until smooth
Drizzle over muffins
Store muffins at room temperature, tightly covered or they also freeze well individually
