Gluten-free Lemon Muffins

Super simple and absolutely delicious. I had to reassure my family that they are gluten-free!

1 1/4 cup Gluten-free flour
1/4 cup corn starch (or tapioca starch)
1 1/2 tsp baking powder
1/2 tsp baking soda
1/4 tsp salt
2/3 cup sugar

2 large eggs
3/4 cup mayonnaise (or sour cream)
6 Tbsp butter, melted
zest and juice of one lemon
1 tsp vanilla extract

Mix for Glaze:
1 cup icing sugar
3 Tbsp lemon juice
1 Tbsp melted butter

Preheat oven to 425 F. 
Mix dry ingredients in large bowl. Mix wet ingredients in a medium sized bowl. Stir them together just until mixed. Fill 12 muffin cups just about full. 
Put them in the hot oven at 425 F for just 3 minutes then reduce the heat to 350 F for 15 minutes.
Cool a few minutes before drizzling with lemon glaze.