Peanut Butter Bars with Chocolate Ganache

Preheat oven 350 Degrees F. Coat a 9x13-inch pan with nonstick spray. For the bars, whisk together flour, baking powder, and salt. Cream peanut butter, butter, and brown sugar with mixer until light and fluffy, 5 minutes. Add golden syrup, eggs, and vanilla and beat until incorporated. Add flour mixture and blend just until combined. Spread batter into prepared pan. Bake bars until a toothpick inserted in the center comes out clean, 25-30 minutes. Let bars cool completely before topping, 1 hour. For the ganache, heat cream in a small saucepan over medium until steaming. Pour cream over chocolate in a bowl, cover, and let sit 5 minutes; whisk until smooth. Pour ganache over bars, then sprinkle with peanuts. Let ganache set up, about 1 hour, then cut into bars.