Prepare the Equipment: Preheat your oven to 350°F (175°C). Generously grease 18 mini muffin cups with non-stick baking spray (specifically one containing flour) or line them with mini paper liners.

Combine the Dry Ingredients: In a medium-sized mixing bowl, whisk together the packed light brown sugar, all-purpose flour, and chopped pecans. Ensure the pecans are fully coated in the flour mixture to prevent them from sinking to the bottom during the bake.

Mix the Wet Ingredients: In a separate small bowl, beat the softened butter and room-temperature eggs together until combined. The mixture may look slightly lumpy or separated, which is perfectly fine.

Form the Batter: Gently pour the wet butter and egg mixture into the bowl of dry ingredients. Fold together with a silicone spatula until just combined. Do not overmix; stop as soon as no dry streaks of flour remain visible.

Fill the Muffin Cups: Using a small spring-loaded cookie scoop or spoon, portion the batter into the prepared mini muffin tin. Fill each cup about two-thirds of the way full.

Bake: Bake in the preheated oven for 20–25 minutes. The muffins are done when the tops spring back lightly when touched and a toothpick inserted into the center comes out clean.

Cool: Allow the muffins to cool in the pan for exactly 5 minutes before carefully transferring them to a wire rack to cool completely. Do not leave them in the pan longer, or the caramelized sugar will stick to the tin.