'- 225 gram (~ 1 1/2 cup) all-purpose flour- 135 gram (~ 1 1/2 cup) oats- 100 gram (~ 1/2 cup) brown sugar- 1/2 teaspoon baking powder- 1/4 teaspoon salt- 8 tablespoon (1 stick) unsalted butter, melted- 1 egg- 1 cup pineapple jam (homemade or store-bought)

1. Preheat oven to 180 Celsius (350 Fahrenheit), and line a 8"x8" square cake pan with parchment paper with an overhang to make it easier to release from the pan later.2. In a large mixing bowl, mix together all-purpose flour, oats, brown sugar, baking powder, and salt. Pour melted butter and mix well, then add the egg and mix again. This is our cookie dough mixture.3. Place 2 1/2 cup of the cookie dough mixture into the prepared pan, press to make the cookie base.4. Spread the pineapple jam over the cookie base, then crumble the remaining cookie dough mixture on top of the jam.5. Bake in the preheated oven for about 40-45 minutes, or until the top is golden brown.6. Remove from oven and let the cookie cool completely in the pan.7. Gently remove cookie from pan (that's why you want the paper overhang, to make this step easy), cut neatly into squares.8. You can cut however large or small you want, from 1"x1" tiny squares (64 tiny squares total), all the way to large 9 squares. Store leftovers in air-tight container.