Start by preheating your oven to 350 degrees.

In a spacious bowl, blend the melted butter with granulated and brown sugar until achieving a creamy consistency.

Introduce vanilla extract and an egg; mix on low until just combined.

Incorporate flour, baking soda, and salt. Mix until the dough comes together as a single ball. Be cautious not to over mix; you can check with your hands to see if it holds together.

Gently add the colorful sprinkles and fold them into the dough.

Shape the cookie dough into balls and bake at 350 degrees Fahrenheit for about 10 minutes. Even if the cookies are soft, remove them from the oven.

Let them cool on the pan for at least 10 minutes before transferring them to a cooling rack for complete cooling. Enjoy your homemade cookies!