This galette is the perfect way to use up some of those zucchinis you have! I love to make this as an appetizer or a light summer dinner, and pair it was a salad and additional protein.
In a large bowl, add flour and salt. Add butter and use your fingers to rub it into the flour. Continue until the butter is incorporated and about pea-sized (it's okay if there are some larger chunks). Add your water, starting with 75g. Use a fork to combine. Add the remaining water, if necessary, until the dough comes together.
Transfer the dough to a lightly floured surface, and mix just enough to form a ball. Do not knead or overwork (this isn't bread).
Shape into a disc and wrap in plastic wrap.
Chill for at least 1-2 hours, or overnight.
Assemble the galette
Line a baking sheet with parchment paper and preheat oven to 400 °F
Thinly slice the zucchinis. Either use a mandoline, or a knife. Place the sliced zucchini on paper towel and salt them. This will help them release extra moisture. Before you add them to the galette, pat them dry.
Once the dough is chilled, transfer it to a lightly floured surface. Roll it out into a large circle or oval, until it's about 1/8" think. Gently transfer it to the baking sheet.
In a small bowl, combine the pesto and ricotta. Spread the mixture in the centre of the dough, leaving about 1" for the crust. Add zest of 1/2 the lemon on top.
Add the zucchini slices. Start in the middle, and add slices in a pinwheel pattern working outwards. Alternate between green and yellow slices.
Fold the crust over the edges of the zucchinis. Brush the crust with the egg.
Bake for 30-40 minutes or until the crust is golden brown.
Allow the galette to cool on the hot baking sheet for about 10 minutes. Sprinkle on the parmesan cheese, zest of the remaining lemon and chunks of goat cheese.