First, preheat your oven to 350 degrees Fahrenheit. While the oven heats up, line a 13x9 inch pan with foil, ensuring that you spray the foil with cooking spray. This will help prevent the bars from sticking and make it easier for you to lift them out later.
Next, in a medium saucepan over medium heat, combine sugar and butter. Stir continuously until the butter is completely melted. Remove the saucepan from heat and let it cool slightly. Cooling is crucial here, as you don’t want to scramble your eggs in the next step!
Once the mixture has cooled a bit, stir in the eggs and vanilla into the sugar and butter mix. Mix well until fully combined. You'll want a smooth consistency that incorporates all the ingredients.
Now, it’s time to add the dry ingredients. Gradually add in the flour, baking powder, and ground nutmeg. Stir until just combined, being careful not to overmix. The mixture will be thick but should be fully incorporated.
Next, fold in the chopped macadamia nuts gently. This adds a wonderful texture and flavor to the bars. Make sure they are evenly distributed throughout the mixture.
Spread the dough evenly in your prepared pan. You might need to use your hands to help spread it out since the mixture is quite thick. Ensure it’s evenly laid out for even baking.
Pop the pan into your preheated oven and bake for about 25 to 30 minutes. You'll know they are done when the edges start to pull away from the pan and the top is lightly browned. Keep an eye on them as every oven can vary!
Once baked, remove the pan from the oven and let it cool in the pan on a wire rack. This cooling step is vital; cutting into them while hot will result in a messy situation.
Once they’ve cooled, cut them into bars or diamond shapes. The cooled Nutty Eggnog Bars will hold their shape beautifully.
To create the glaze, in a small bowl, combine powdered sugar, vanilla, and 2 tablespoons of eggnog. If the mixture is too thick, add more eggnog a teaspoon at a time until you reach a piping consistency. Use a piping bag or a Ziploc bag with a snipped corner to drizzle the glaze over the cooled bars. Let it set before serving.
