Follow these simple steps to bake your perfect batch of Easy Marshmallow Cookies:

1. Preheat & Prep: Preheat your oven to 375°F (190°C). Line two large baking sheets with parchment paper or silicone baking mats to prevent sticking, especially important with melting marshmallows.
2. Cream Butter & Sugars: In a large mixing bowl, using an electric mixer (handheld or stand mixer with paddle attachment), cream together the softened unsalted butter, granulated sugar, and packed light brown sugar on medium speed until the mixture is light, fluffy, and pale in color. This usually takes about 2-3 minutes. Scrape down the sides of the bowl occasionally.
3. Add Eggs & Vanilla: Add the large eggs one at a time, beating well after each addition until fully incorporated. Beat in the pure vanilla extract until combined.
4. Combine Dry Ingredients: In a separate medium bowl, whisk together the all-purpose flour, baking soda, and salt. This ensures the leavening agent and salt are evenly distributed.
5. Mix Wet & Dry: Gradually add the dry ingredient mixture to the wet ingredients in the large bowl. Mix on low speed until just combined. Be careful not to overmix at this stage; stop as soon as you no longer see streaks of flour. Overmixing can lead to tough cookies.
6. Fold in Marshmallows: Gently fold in the mini marshmallows using a spatula or wooden spoon. Try to distribute them evenly throughout the dough, but don’t worry if it’s not perfect.
7. Scoop Dough: Drop rounded tablespoons of cookie dough onto the prepared baking sheets, leaving about 2 inches between each cookie to allow for spreading. A medium cookie scoop (about 1.5 tablespoons) works perfectly for uniform cookies. Optional but Recommended: If time permits, chill the scooped dough balls on the baking sheet in the refrigerator for 15-30 minutes. This helps prevent excessive spreading and intensifies the flavor.
8. Bake: Bake in the preheated oven for 9-12 minutes. The edges should be lightly golden brown, and the centers should still look slightly soft and puffy. The marshmallows will puff up and might lightly toast. Keep a close eye on them, as oven temperatures can vary. For chewier cookies, err on the side of slightly underbaking.
9. Cool: Let the cookies cool on the baking sheets for 5-10 minutes before transferring them to a wire rack to cool completely. The marshmallows will be very hot and molten right out of the oven, and this cooling time on the sheet allows the cookies to set properly.
10. Enjoy: Serve warm for the ultimate gooey marshmallow experience, or store and enjoy once completely cooled.