Step 1

In a bowl, mix softened butter with sugar until smooth. Add 1 egg yolk and vanilla extract, and mix until incorporated.

Step 2

Sift in flour, baking soda, and baking powder. Mix until all the flour disappears.

Step 3

Wrap the dough in plastic wrap and roll into an even log. Refrigerate for 20-30 min to allow it to firm up.

Step 4

After 20-30 mins, remove the plastic wrap and cut it into 8 even pieces. I used a kitchen scale to make sure each piece was the same weight but that's optional!

Step 5

Roll each piece into a ball, then press it flat in between plastic wrap until it’s 1/4 inch thick. Repeat with the rest.

Step 6

Preheat your oven to 375F (convection off). Separate the Hawaiian sweet rolls, and place on a wire rack on a baking tray (this ensures the bottoms don't burn). Lay a cookie topping on each roll. Using a butterknife, gently indent a crosshatch pattern (optional) but don’t cut all the way through.

Step 7

Whisk or beat an egg in a bowl, and lightly brush the cookie tops with this egg wash.

Step 8

If your oven uses convection heat (it distributes heat with a fan), you may want to use aluminum foil to create a protective wall around your baking tray to prevent your rolls from getting too toasty.

Step 9

Bake for 13-15 min or until cookie tops are golden. They’re best enjoyed slightly warm!