1. In a medium heavy bottom pot, whisk cornstarch, ½ cup sugar and ¼ teaspoon salt together.
2. In a separate bowl whisk 2 cups Evaporated Milk and egg yolks to combine thoroughly.
3. Add milk mixture to the pot and place pot over medium heat stirring constantly to prevent lumps from forming. Bring mixture to a boil and continue to boil for about 1 minute.
4. Remove from heat and add 1 teaspoon vanilla essence and 2 tablespoons butter. Cover completely by pressing plastic wrap onto top of pastry cream to prevent skin from forming and refrigerate.
For Cupcakes
5. In an electric mixer cream 1 cup of butter and 2 cups granulated sugar until light and fluffy.
6. Add eggs one at a time, beating well in between additions.
7. Sift flour, baking powder and ½ teaspoon salt in to a medium bowl.
8. Add 2 teaspoons vanilla extract to 1 cup Evaporated Milk and set aside.
9. Add flour mixture and milk mixture to creamed butter alternating the additions. Beginning and ending with the flour mixture.
10. Beat until ingredients are combined thoroughly. Pour batter into lined cupcake pans.
11. Bake in a preheated oven at 350°F (180°C) for 15 – 20 minutes or until a wooden pick comes out clean when inserted.
12. Leave to cool on a wire rack for 10 minutes. Using a small knife, cut out a hole about one inch deep in the centre of each cupcake.
13. Pipe pastry cream into hole and continue to cover top of each cupcake with pastry cream. Sprinkle sugar onto pastry cream topped cupcakes generously.
14. Using a kitchen torch or broiler, caramelize the sugar on each cupcake.