Prepare the Crust: Begin by crushing 15 oz of shortbread cookies until they resemble sandy crumbs. Blend them with melted butter until well combined, then press this mixture firmly into a lined baking pan to form a solid base for your bars.
Add Raspberry Preserves: Next, spread the seedless raspberry jam evenly over the crust, ensuring it reaches all edges for maximum flavor in every bite.
Pour the Condensed Milk Mixture: Pour sweetened condensed milk evenly over the jam layer, swirling it gently with a spatula for an even distribution that enhances both taste and texture.
Layer with Coconut and Nuts: Sprinkle shredded coconut and chopped pecans on top of the condensed milk mixture, pressing down slightly so they adhere well.
Top with Chocolate Chips: Scatter semisweet chocolate chips and white baking chips on top of your layered ingredients, reserving some white chips for later if desired.
Bake and Cool: Bake in a preheated oven at 350°F (175°C) for about 25-30 minutes until golden brown and aromatic. Allow the bars to cool in the pan before cutting them into squares to set flavors perfectly.