In a saucepan over medium heat, melt the European-style unsalted butter, stirring frequently for about 10-15 minutes until it turns a golden brown and develops a nutty aroma. Remove from heat and let cool to room temperature.

Open the canned pumpkin and blot it on paper towels to remove excess moisture. Set aside.

In a medium bowl, whisk together the all-purpose flour, pumpkin spice blend, baking soda, and salt. Ensure there are no lumps.

In a large mixing bowl, combine the cooled brown butter, light brown sugar, pure maple syrup, and egg yolk. Mix until well blended and creamy. Add the prepared pumpkin, vanilla extract, and maple extract if using, stirring until smooth.

Gradually stir the dry ingredients into the wet mixture until just combined. Be careful not to overmix.

Cover the bowl with plastic wrap and refrigerate for at least 8 hours or overnight.

Preheat your oven to 350°F (177°C) and line baking sheets with parchment paper.

Using a cookie scoop, scoop out portions of chilled dough and roll into balls. Roll each ball in granulated sugar and place on the prepared baking sheets, spacing them about 2-3 inches apart.

Bake for 12-14 minutes, checking for puffiness around the 9-10 minute mark. They should be lightly golden on the edges but still soft in the center.

Allow the cookies to cool on the baking sheets for 5 minutes before transferring to a wire rack to cool completely.