Preheat the Oven: Preheat your oven to 350°F (175°C). Line your baking sheets with parchment paper or silicone mats to prevent the cookies from sticking.
Prepare the Rhubarb: If using fresh rhubarb, wash it thoroughly and chop it into small, bite-sized pieces. If using frozen rhubarb, make sure it’s thawed and drained of excess moisture.
Cream Butter and Sugar: In a large mixing bowl, cream together the softened butter, granulated sugar, and brown sugar until light and fluffy. Use an electric mixer or hand whisk for best results.
Add Eggs and Vanilla: Beat in the eggs one at a time, ensuring each one is fully incorporated. Add the vanilla extract and mix until smooth.
Mix Dry Ingredients: In a separate bowl, whisk together the flour, baking soda, salt, and cinnamon.
Combine Wet and Dry Ingredients: Gradually add the dry ingredients into the wet ingredients, mixing just until combined.
Fold in Rhubarb: Gently fold the chopped rhubarb into the cookie dough using a spatula. Be careful not to overmix to preserve the texture.
Scoop the Dough: Using a cookie scoop or tablespoon, drop spoonfuls of dough onto the prepared baking sheets. Space the cookies about 2 inches apart.
Bake: Bake the cookies in the preheated oven for 12-15 minutes or until the edges are golden brown and the center is set. Keep an eye on the cookies to ensure they don’t overbake.
Cool the Cookies: Allow the cookies to cool on the baking sheets for 5 minutes, then transfer them to a wire rack to cool completely.
