Preheat oven to 350°F. Grease your mini muffin tin.

In medium bowl, combine the flour, baking soda, and salt. Set aside.

Using a stand mixer, mix together the softened butter and both sugars until light, smooth and fluffy, about 2 to 3 minutes. Add the eggs, one at a time, mixing well after each addition. Add the vanilla until fully combined. Add the flour mixture and mix until well combined.

Using your hands, roll the cookie dough into tablespoon sized balls. Place them in the mini-muffin pan and bake for about 10-12 minutes, or until golden brown but not too dark around the edges.

When finished, remove them from the oven and let sit for about 2 minutes. Using a small spoon or butter knife, make little wells in each cookie muffin and place your desired chocolate inside and press down gently.

Alternatively, you can place a couple mini marshmallows inside and then place your chocolate candy inside and press down gently. Then, as it starts to melt a little, place a few mini marshmallows on top to stick to the chocolate.

Let cool for about 10 minutes in the pan and gently remove using your hands or a fork. Drizzle with melted Nutella if desired and serve.