Chickpea fries are a real French classic. Custardy on the inside with a delicate exterior crunch, they make a delightful snack or side dish. (Note: Allow four to six hours for chickpea mixture to set during cooking process.)
In a large stockpot, bring water to a boil; add milk, salt, and a few grinds of pepper and allow the heat to come back up to a simmer. Meanwhile, heat a dry skillet over medium heat. When it's warm, add coriander, fennel seeds, and black peppercorns; toast to release the oils and aromatics, shaking the skillet to avoid burning. Place red pepper flakes in a mortar, then add the warmed spices. Use pestle to crush and grind the spices. Add the spice mix to the simmering milk and water; then add butter and 2 tablespoons of olive oil.
When the milk begins foaming, add the chickpea flour, whisking vigorously to avoid clumping; lower the heat to allow the mixture to cook slowly. As it cooks, it will thicken. Mince a clove of garlic, add it to the mixture, and let it simmer for another 10-12 minutes.
When the chickpea mixture is thickened and cooked, turn off the heat and pour the mixture into a 9x13-inch rimmed baking sheet lined with parchment paper. Once the mixture is no longer steaming, lay another sheet of parchment on top and chill to set, at least four hours and up to overnight.
Heat 3 cups olive oil in a medium saucepan over medium-high heat until the temperature reaches 340-350 degrees F. Meanwhile, cut chilled, set chickpea mixture into large "fries." Gently place chickpea fries into the hot oil and cook until brown and crispy-looking on the outside, 1–2 minutes. (Do the first few one at a time, moving the pan on and off the heat, to determine how quickly the fries cook.) Remove the fries with a slotted spoon, set aside on paper towels to drain, and sprinkle with salt.
Chiffonade the basil leaves. Spread the basil on a plate, top with chickpea fries, sprinkle with additional basil, and serve.