Line an 8x8 metal pan with parchment paper and lightly mist with nonstick spray.

Beat 3/4 cup softened butter, 3/4 cup brown sugar, and 1/2 cup granulated sugar for 2 to 3 minutes until light, fluffy, and pale.

Mix in 1 egg, 1 egg yolk, 1 1/2 teaspoons vanilla extract, and 1/4 teaspoon almond extract until smooth and creamy.

Add 2 cups flour, 1/2 teaspoon baking soda, 1/2 teaspoon baking powder, and 1/2 teaspoon salt. Mix on low until a thick, soft dough forms.

Gently fold in 1/2 cup pastel jimmies.

Press the dough evenly into the prepared pan. Smooth the top with a spatula.

For thicker, puffier bars, chill the pressed dough in the pan for 20 to 40 minutes. (I chilled mine for 30 minutes.) Skip chilling for a softer, gooier center.

Bake at 350 degrees F for 26 to 32 minutes, until the edges are lightly golden, the top is set, and the center no longer looks shiny.

Cool at least 45 minutes before lifting out and slicing or adding frosting.

For the frosting: Beat 1/2 cup softened butter for 1 to 2 minutes until smooth. Add 1 1/2 cups powdered sugar, 1 to 2 tablespoons milk, 1 teaspoon vanilla, and a pinch of salt. Mix on low, then beat on medium-high for 2 to 3 minutes until fluffy.

Add a tiny drop of green food coloring and mix until the color is even. Adjust with more powdered sugar for thickness or milk for a softer spread.

Spread the frosting over the completely cooled cookie bars and top with extra pastel sprinkles.