Step 1: Preheat the oven to 350°F (175°C).
Step 2: Line your 9x13 inch baking pan with parchment paper.
Step 3: In a large mixing bowl, cream together the butter and sugar until light and fluffy. Add the vanilla extract and mix until combined.
Step 4: In a separate bowl, whisk together the flour, baking powder, and salt. Gradually add this dry mixture to the creamed butter and sugar, stirring until just combined.
Step 5: Set aside a portion of the dough for the streusel. Mix in the rolled oats and crumble it together until you achieve a crumbly texture.
Step 6: Press the remaining dough firmly into the bottom of the prepared baking pan. Bake for about 10-12 minutes.
Step 7: Remove the base from the oven. Sprinkle the chocolate chips over the warm crust, then drizzle the caramel sauce over the chips.
Step 8: Crumble the reserved dough mixed with oats over the top.
Step 9: Return to the oven and bake for another 20-25 minutes.
Step 10: Let the bars cool in the pan for at least 15 minutes before lifting out and cooling completely on a wire rack.
