Combine the flour, sugars, baking powder, and salt in a bowl
In another bowl mix together the egg, milk, melted butter and vanilla
Add the liquid into the dry ingredients, stirring just until moistened
Put half the batter into the greased muffin cup. Add a generous 1 tsp jam in center of each muffin and then fill the muffin cup with the remaining batter. Muffin tin should be about ⅔ full.
Bake at 400 degrees for 20 minutes or until a toothpick comes out clean
Cool for 5 minutes and then remove from pan onto a rack
