Roll out the crust on a lightly floured surface to a 12-inch (25 cm) round about ⅛ inch (3 mm) thick. Gently transfer the crust to a 9-inch (22 cm) pie dish. Trim any excess dough around the edges. Fold the edges of dough back underneath itself, then crimp using an index finger knuckle on one hand and the thumb and index finger on the other hand.
Place a piece of parchment paper in the center of the crust. Add the dried beans to the center and spread toward the sides of the crust — this will add weight to keep the crust from puffing up and hold up the walls while baking.
Bake the crust for 15 minutes. Carefully remove the weights by lifting out the parchment paper, then bake for 5 minutes more, until the dough no longer looks raw. Remove from the oven and let cool.
While the crust bakes, make the filling: Set the tofu in a fine-mesh strainer set over a bowl. Let drain for 10 minutes.
In a large skillet, combine the water, broccolini, and ¼ teaspoon salt. Cover and steam over medium-high heat for 2–3 minutes, until the broccolini is bright green and tender. Remove the pan from the heat and set aside.
Heat 2 teaspoons of olive oil in a medium pan over medium heat until just shimmering. Add the onion and ¼ teaspoon salt. Sauté for 3–4 minutes, until the onion is translucent. Remove the pan from the heat and set aside.
Crumble the tofu into a blender. Add the chickpea flour, oat milk, coconut oil, turmeric, garlic powder, kala namak, remaining teaspoon of salt, the cornstarch, miso, and nutritional yeast. Blend on high speed for 60–90 seconds, until completely smooth, scraping down the sides as needed. Transfer the mixture to a medium bowl.
Season the filling with the pepper. Set aside a few larger pieces of broccolini for topping, then fold the rest of the steamed broccolini and sautéed onions into the “egg” mixture.
Pour the mixture into the prepared crust. Arrange the reserved broccolini on top.
Cover the quiche with aluminum foil and bake for 35 minutes. Remove the foil and bake for another 10–15 minutes, until the quiche is set and no longer jiggling in the center and the crust is beginning to brown. Let cool for 30 minutes before slicing.
Garnish the quiche with the chives, then slice and serve.