01 - Preheat oven to 350°F. Line a 9x13-inch baking pan with parchment paper, allowing overhang for easy removal.
02 - In a large bowl, beat softened butter and granulated sugar together until light and fluffy.
03 - Mix in eggs one at a time, then incorporate vanilla extract until fully combined.
04 - In a separate bowl, whisk together all-purpose flour, baking powder, and salt.
05 - Gradually blend dry ingredients into wet mixture, mixing just until dough forms.
06 - Press two-thirds of the dough evenly into the bottom of the prepared pan.
07 - Spread strawberry jam uniformly over the dough base, leaving a small border around edges.
08 - Crumble remaining dough over jam layer and press gently to adhere.
09 - Bake for 23–27 minutes until edges turn golden and center sets completely.
10 - Let bars cool entirely in the pan on a wire rack before glazing.
11 - Whisk powdered sugar, milk, and vanilla extract until smooth and pourable.
12 - Drizzle glaze over cooled bars and immediately sprinkle with colorful toppings.
13 - Allow glaze to set for 15 minutes, then cut into individual bars.