These light and airy pumpkin streusel muffins taste entirely homemade but will save you time since they are made with a cake mix base. Any brand of spice cake mix will work as long as it is 15.25 ounces.
Prepare the streusel topping first. In a small bowl, mix together the softened butter, brown sugar, and flour until it forms small, course crumbs. Set aside.
To prepare muffins, add the spice cake mix, pumpkin, eggs, water, and vegetable oil in a large mixing bowl. Use an electric mixer and mix on low for about 30 seconds followed by 1 minute at medium speed. Otherwise, mix with a whisk by hand until all ingredients are thoroughly combined for about 2 minutes.
Line your muffin tins with baking cups, and fill the liners with batter so they are no more than ⅔s full. Sprinkle the streusel evenly over all muffin batter.
Bake the muffins in preheated oven for about 20-24 minutes. All ovens vary, so test for doneness after about 20 minutes as not to overbake. Carefully remove the muffins once done and let finish cooling on a wire rack.
Notes
The muffins may be stored at room temperature for up to 3 days. Leftover muffins also freeze well to be enjoyed at at later date.