Preheat oven to 350 degrees.
Cream together softened butter that is very soft but not melted with the brown sugar and sugar until light and creamy. Add egg, egg yolk, vanilla, and almond and mix until combined.
Add in flour, cornstarch, baking soda, and salt and beat until combined.
Fold in the chocolate chips and white chips.
Separate the dough in half. I put half of the dough on a plate and spread it out with my hands about 1 inch thick. With 1 1/2 tablespoons of jam I put tiny little dollops of jam all over the dough. Then I cut it in carefully with a butter knife. Don't stir it in or your dough will turn pink.
Roll carefully into balls using about 2 to 3 tablespoons of dough per cookie.
Place on a cookie sheet lined with parchment paper. Gently press down on the top of each cookie. (not a lot, just so that it's not a perfect ball anymore). Chill the dough balls for 15 minutes and then bake in the oven for 11 to 12 minutes.
Remove from oven and let cool on the pan for about 5 minutes, then transfer to a cooling rack.
Then repeat with the other half of the dough, spreading the jam throughout the dough, refrigerating, then cook. You should get about 12 large cookies. 6 cookies out of each half of the dough.