Preheat oven to 350 F. Grease two 12-cup muffin tins.
Combine all ingredients in one bowl and mix with wooden spoon until incorporated.
1 box vanilla cake mix, 3 eggs, 1 cup shredded zucchini, 1 teaspoon vanilla extract, 1 Tablespoon unsalted butter, 1/2 cup chopped walnuts, 1/2 cup golden raisins
Divide batter between 12-18 muffin cups (For 18 small muffins fill cups halfway, for 15-16 larger muffins, fill cups 3/4 full).
Place muffin tin on a baking sheet and bake in preheated oven for 25 minutes.
Cool in pan ten minutes, then remove from pan and cool completely on wire racks.
Place cooling rack of muffins over a sheet of waxed paper. Whisk together glaze ingredients. Drop one tablespoon of glaze on the top of each muffin and allow glaze to drizzle down. Waxed paper will catch the drips. Allow glaze to set up before serving.
You will need 1 heaping cup of shredded zucchini for this recipe, which should equal about 1 medium zucchini. You can also use that shredded zucchini that you stuck in the freezer from your bountiful harvest last year! If using frozen, be sure to thaw it and pat it of excess moisture with a paper towel before beginning.
Feel free to use any brand of vanilla cake mix you like here, though I would recommend the type that uses oil and eggs as that is what I've had success with and what this recipe was built around. I opted for Betty Crocker Vanilla mix for mine.