Preheat your oven to 350°F (175°C). Prepare your muffin tin by greasing or lining it.

In a large mixing bowl, whisk together the eggs, vegetable oil, sugar, and vanilla until smooth and creamy.

Stir in the grated zucchini and well-drained crushed pineapple, folding until just incorporated.

In a separate bowl, whisk together the flour, baking soda, baking powder, cinnamon, and salt until free of lumps.

Gently fold the dry ingredients into the wet mixture until just combined, retaining some flour streaks.

Add the coarsely chopped walnuts, folding them into the batter without overworking it.

Fill each muffin cup about 3/4 full, ensuring even levels for uniform baking.

Bake for 18-22 minutes. Check for doneness by inserting a toothpick in the center; it should come out clean or with a few moist crumbs.

Cool in the tin for 5 minutes, then transfer to a wire rack to cool completely before enjoying.