1 1/2 to 2 cup oven-safe mug
2 tablespoons granulated sugar
1 teaspoon cornstarch
1/4 teaspoon nutmeg
Mix sugar, cornstarch, raisins and nutmeg, then put into a small zip-type plastic bag. Line the mug with tissue paper in a coordinating color, then place the plastic bag inside the mug. Place the mug on a square of colored cellophane, add some ribbon to tie at the top, and add a gift tag with the following instructions:
1 cup milk
Custard mix from bag
1/2 teaspoon vanilla extract
1 beaten egg yolk
Heat oven to 325 degrees F/165 degrees C.
Bring the milk to a simmer in a medium pan.
Mix well the custard mix from the bag with vanilla extract and egg yolk. Add 1 tablespoon of the milk to the powder, mix well, then slowly add the remaining milk.
Pour the mix into the mug, and bake for 15 minutes.