Peppermint Extract

• Peppermint extract is the best way to add the strongest flavor of mint to your cookies. You can control the amount, and the addition of extract does not alter the baked quality of the cookie. Find peppermint extract, which is alcohol infused with peppermint leaves, in the baking aisle at the grocery stores. Most recipes call for 1/4 teaspoon of peppermint extract. Add more if you want a stronger flavor, and whisk it into the wet ingredients before you include the dry ones.

Peppermint Oil

• Peppermint oil is the much stronger cousin of peppermint extract. It is created by infusing the herb into a food-safe and neutral oil. Substitute one part peppermint oil for every four parts peppermint extract in a recipe. If your recipe has no directions for adding oil or extract, use just two drops of oil, whisking it into the wet ingredients.

Fresh Mint-Infused Ingredients

• Infuse recipe ingredients with fresh mint. For example, create a simple syrup by simmering one part mint with one part sugar and one part water. Cool and strain the mixture and use it in lieu of an equal amount of liquid and sugar within the recipe. Alternatively, for cookies with milk in them, simmer the milk with an equal amount of fresh mint for three to five minutes, or to taste. Let it cool before adding it to wet ingredients in the recipe.

Mint Tea-Infused Cookies

• If fresh mint, extract or oil are unavailable, add mint tea. Brew a cup of tea with four to five teabags, leaving them in for the time called for on the package. If they are left in too long, the tea turns bitter. Remove the bags and use 1 to 2 tablespoons of the tea in your cookie recipe, adding as much or as little according to the flavor you desire.