Preheat your oven to 350°F (175°C). This initial step ensures that your Fudgy Pumpkin Bars bake evenly. While the oven heats, line an 8-by-8-inch baking pan with aluminum foil and spray it with cooking spray to prevent sticking. This preparation is crucial for easy removal later on.
In a large, microwave-safe bowl, combine the white chocolate chips and unsalted butter. Heat the mixture in the microwave for about 2 minutes on high power. Be sure to stir after the first minute, then continue heating in 20-second intervals, stirring frequently. The goal is to achieve a smooth consistency without scorching the chocolate, which can happen easily.
Once melted, let the mixture cool slightly before adding the egg. This step is essential to avoid scrambling the egg. After allowing it to cool for a moment, whisk in the egg, granulated sugar, and vanilla extract until fully combined.
Next, add the pumpkin puree, pumpkin pie spice, and cinnamon to the mixture. Whisk these ingredients together until they're well incorporated. The spices will fill your kitchen with a wonderful aroma, reminiscent of fall.
Now, it's time to add the dry ingredients. Gently fold in the all-purpose flour and a pinch of salt until just combined. Be cautious not to overmix; you want a tender texture.
Pour the batter into your prepared baking pan, smoothing the top with a spatula for an even bake. This step is important for achieving that characteristic fudgy texture. The batter should be thick and luscious, promising a delightful treat.
Bake the bars in your preheated oven for about 30 minutes, or until a toothpick inserted into the center comes out mostly clean. You might want to check at around 25 minutes to ensure they don’t overbake. The edges should look set, with a slight jiggle in the center.
While the bars are baking, prepare the glaze. In a small saucepan, melt another ¼ cup of unsalted butter over medium-high heat. Watch closely as it turns a deep amber color, which takes about 5 minutes. The butter should bubble and foam; stir occasionally to monitor the browning process. This nutty aroma is what you're aiming for!
Once browned, immediately transfer the butter, including the flavorful brown bits, to a mixing bowl. Add the confectioners’ sugar, vanilla bean paste, and a pinch of salt. Slowly mix in the cream or milk until the glaze reaches your desired consistency. It should be smooth and pourable.
After your bars have cooled for about 10 minutes, pour the glaze over them while they're still warm. Use a spatula to spread it evenly, allowing it to flow into every nook and cranny. Let the bars cool completely in the pan, uncovered, for at least 2 to 3 hours, or overnight if you can resist the temptation!
