Grate the zucchini and squeeze out all moisture using a towel or cheesecloth to avoid a soggy slice.

Preheat oven to 375°F (190°C). Grease and line an 8x8-inch pan with parchment, leaving an overhang.

In a large bowl, stir together flour, zucchini, cheese, raisins, oregano, salt, and pepper.

Whisk eggs, milk, and olive oil in a separate bowl until smooth.

Add wet to dry. Fold gently until just combined. The batter should be thick and scoopable.

Spread into the pan and bake for 35–40 minutes, until golden and a toothpick comes out clean.

Cool in pan for 10 minutes, then transfer to a rack. Slice and serve warm or at room temp.