These baked donuts are moist, flavourful , gluten-free, and a great way to use up zucchini from your garden!
Preheat oven to 350°F.
Lightly coat donut pan(s) with cooking spray and flour.
In a large bowl, whisk together dry ingredients.
In separate bowl, stir wet ingredients until well-combined, then gently mix in zucchini.
Add wet ingredients to dry, mixing just until smooth. Go gently as over-mixing can lead to dry donuts.
Transfer batter to Ziploc bag and cut the bottom corner tip off (or piping bag with extra large round tip). This makes it easy to pipe into donut pan. Or, simply use a spoon. Fill each well ¾ full without covering middle section (so you're left with a hole after baking).
Bake for 12 minutes, or until edges are golden brown and top springs back when lightly touched. Allow to cool for 5 minutes in pan, then transfer donuts upside down onto cooling rack. Completely cool before glazing.
In a small bowl, mix powdered sugar with vanilla. Slowly add milk (start with 1 tablespoon), and stir until smooth. Add a bit more powdered sugar if glaze becomes too runny.
Dip bottom of donuts into glaze, then place glazed-side up onto rack to drip dry. Place parchment paper or baking sheet below to catch drippings. Allow to set up, then transfer to airtight container.