The addition of different amounts of a functional ingredient composed of water, inulin, chia seeds, and hemp or flaxseed oil was examined as butter replacer to improve the nutritional value of muffins. Nutritional, technological, and sensory characteristics of the reformulated products were assessed, as well as the stability under storage at room temperature. One control and six modified formulations with three levels of butter replacement (50%, 75%, and 100%) were analyzed. Modified muffins improved their nutritional profile, reducing up to 78% of fat and increasing fiber (up to 62.5%) and omega¿3 fatty acids content (from 0.12 g/100 g of product to 0.62 g and 1.55 g in hemp and flaxseed oil samples, respectively). Sensory analysis revealed that flaxseed oil samples were indistinguishable from the control in all evaluated attributes, even in the highest level of replacement. During storage, texture of modified samples behaved similar to the control and no oxidation problems were observed in any of the formulations. Therefore, the functional ingredient proved to be a feasible alternative for replacing butter in muffins, preserving the quality attributes and making them healthier foods.