Cream together melted unsalted butter, granulated sugar, and brown sugar until light and fluffy.

Add eggs and vanilla extract; mix on low speed until blended smoothly.

Sift together all-purpose flour, cinnamon powder, baking soda, baking powder, and cornstarch. Gradually add to wet ingredients, stirring gently.

Fold in chopped toasted pecans and optional toffee bits until evenly distributed.

Cover and chill the dough in the refrigerator for 30–45 minutes.

Preheat oven to 350°F (175°C) and line a baking tray with parchment paper.

Use a cookie scoop to form balls of dough and place them 2 inches apart on the baking tray.

Bake for 11–14 minutes until edges are golden and centers are soft.

Allow cookies to cool on the tray for about 5 minutes before transferring to a wire rack.