In a small saucepan, pour in the milk and bring it to a boil over medium to high heat
In a separate deep saucepan, combine the egg yolks, cornstarch, and sugar
Slowly pour in ¼ cup of the hot milk into the egg mixture, whisk as you go to prevent the eggs from curdling due to the heat from the milk
Pour the remaining milk and whisk it all well
Place the saucepan over medium to high heat, continue to whisk, and bring it to a boil
Whisk the creamy mixture constantly for 2 to 5 minutes until it thickens, remove from stove
Combine vanilla and almond extracts into the cream pastry
Cut up the butter into cubes and whisk them in one at a time until fully incorporated
Place the pastry into a bowl and cover with plastic wrap to prevent any skin from forming
Place the bowl into the fridge and let it cool for a couple of hours