In a large mixing bowl, combine 1 cup of melted unsalted butter, ¾ cup of granulated sugar and ¾ cup of light brown sugar. Blend until smooth and creamy using a hand mixer on medium speed for 2-3 minutes.

Add in 1 large egg and 1 teaspoon of pure vanilla extract. Mix on low speed until fully incorporated, about 30 seconds.

Gradually add 2 ½ cups of all-purpose flour, 1 teaspoon of baking soda, and ½ teaspoon of salt. Mix on low speed until just combined, creating a soft dough.

Gently fold in 1 cup of chocolate chips and ½ cup of Halloween sprinkles using a spatula until evenly distributed.

Form equal-sized, 2-tablespoon balls of dough and place them on a parchment-lined baking sheet. Cover and chill in the refrigerator for 1.5 to 2 hours.

Preheat your oven to 350℉ (175℃). Keep the dough refrigerated until ready to bake.

Place chilled dough balls on a new parchment-lined baking sheet, spacing them about 2 inches apart. Bake for 11-13 minutes until edges are golden.

Press candy eyes onto each warm cookie when removed from the oven. Let them cool for about 5 minutes, then transfer to a wire rack.