Instructions

• Preheat oven to 350°F. Spray mini muffin pan(s) with nonstick cooking spray and set aside.
• In the bowl of a stand mixer or a large mixing bowl with a hand mixer, cream the softened butter and granulated sugar on medium speed until smooth and fluffy, about 1 minute. Scrape down the bowl as needed.
• Add the egg and vanilla extract and mix until just combined.
• Add the baking soda, salt, and cream of tartar and mix briefly until incorporated.
• Add the all-purpose flour and mix on low speed until a soft cookie dough forms. Do not overmix; scrape the bowl if needed.
• Using a tablespoon measure, scoop level 1-tablespoon portions of dough (or use a tablespoon scoop) and place one dough ball into each mini muffin cavity. Gently flatten each ball slightly so it sits evenly in the cavity.
• Bake for 18–20 minutes, or until the cookies are no longer glossy and the edges are lightly golden.
• Immediately after removing the pan from the oven, use the handle of a wooden spoon or the back of a teaspoon to press a shallow cavity into the center of each warm cookie to form the tart shell. Press gently and re-shape while the cookies are still warm if needed.
• Let the tart shells cool completely in the pan. Once cooled, remove them from the pan by nudging each with a butter knife.
• Spoon 1–2 teaspoons lime curd into the center of each cooled tart shell.
• Store filled tarts in an airtight container in the refrigerator for up to 3 days. Freeze unfilled tart shells in an airtight container for up to 3 months; thaw before filling.