Cranberry Orange Crumble Muffins

0 Melt butter over moderately low heat (or in microwave). Whisk in milk, egg, yolk, orange zest, fresh squeezed orange juice and vanilla until well combined.
1 In separate bowl, whisk flour, sugar, baking powder and salt. Add milk mixture and stir until just combined.
2 Gently but thoroughly fold in cranberries. Divide batter among muffin cups.
3 Combine all topping ingredients into a bowl and rub together with fingertips until crumbly. Sprinkle evenly over batter in cups.
4 Bake 375 degrees until golden and wooden pick comes out clean, about 15-20 minutes. Cool in pan on rack for 15 minutes than run knife around edges of muffin cups and carefully remove from pan.