Step 1

Arrange a rack in the middle of the oven and heat the oven to 350°F.

Step 2

Grate 2 pounds zucchini on the large holes of a box grater (about 6 cups) into a colander set over a large bowl. Sprinkle with 1/2 teaspoon of the kosher salt and toss to combine. Set aside to drain for 15 minutes.

Step 3

Spread 1/4 cup raw hazelnuts out in an even layer on a rimmed baking sheet. Transfer to the oven and toast, stirring occasionally, until fragrant and golden-brown, 8 to 10 minutes.

Step 4

Meanwhile, dice 1 large shallot. Smash and peel 1 small garlic clove. Finely grate the zest of 1 small lemon. Halve the zested lemon and reserve.

Step 5

When the zucchini is ready, press on it with your hands or a wooden spoon to push out some of the liquid. Transfer the zucchini to a clean kitchen towel, wrap it up, and squeeze out as much water as you can to get it as dry as possible. You should have about 3 cups.

Step 6

Wrap the toasted hazelnuts in a clean kitchen towel and rub vigorously to remove as much of the skins as possible (don’t worry about any skin that doesn’t easily come off). Transfer the nuts to a cutting board and coarsely chop.

Step 7

Heat 1/4 cup olive oil in a large, high-sided sauté pan over medium heat until shimmering. Add the shallot and cook, stirring occasionally, under softened and translucent, 2 to 3 minutes. Add the zucchini, the remaining 1/2 teaspoon kosher salt, and 1/4 teaspoon black pepper. Cook, stirring occasionally, until the zucchini cooks down, caramelizes, and softens considerably, about 15 minutes. Reduce the heat if the zucchini starts to burn. The mixture should be jammy and spreadable. Remove from the heat.

Step 8

Toast 4 thick bread slices, then rub one side of each slice with the garlic clove. Divide the zucchini butter between the garlic-rubbed toast and spread out evenly in a thick layer. Garnish with the hazelnuts, fresh basil or mint leaves, and a pinch or two of Aleppo pepper and flaky salt. Squeeze the juice of the reserved lemon halves over the toasts and serve.