In a large mixing bowl, beat the softened butter and granulated sugar together until the mixture is light and fluffy. This should take about two to three minutes using a hand mixer or a stand mixer. Ensuring the butter is properly aerated will give your shortbread that classic, tender crumb.
Stir in the alcohol-free vanilla until well incorporated. Gradually add the all-purpose flour and salt to the butter mixture. Mix on low speed just until a soft dough forms. Be careful not to overmix at this stage, as overworking the dough can lead to a tough cookie rather than a crumbly shortbread.
Gently fold in your festive sprinkles by hand using a spatula. This ensures they are evenly distributed without breaking them or streaking the dough with color. The bright reds and greens will look beautiful against the pale dough.
Turn the dough out onto a piece of parchment paper and press it into a square that is roughly half an inch thick. Use a sharp knife or a pizza cutter to slice the dough into small half-inch squares. You do not need to separate them significantly on the baking sheet because shortbread does not spread much during baking.
Place the bites on a baking sheet lined with parchment paper. Bake at 325 degrees Fahrenheit for 12 to 15 minutes. You are looking for the bottoms to be just barely golden while the tops remain pale. Let them cool completely on the pan so they set properly before moving them.
