Preheat oven to 425 degrees.
In a medium mixing bowl, add tahini, lemon juice, maple syrup and garlic. Whisk to combine. Slowly add water until creamy and pourable. Season with salt, to taste; and set aside.
Cut 1 head cauliflower into florets; toss with 2 tablespoons olive oil on a large rimmed baking sheet; season with salt and freshly ground black pepper. Roast, tossing occasionally, until almost tender, 30-35 minutes.
Meanwhile, bring 1-inch of water to a boil in a large pot. Have a large bowl of ice water ready. Steam ears of corn in the boiling water for 4 minutes. Using tongs, remove the corn and plunge it into the ice water until cool. Drain excess water from the ears. Place an ear of corn, stem side down, on a cutting board, holding it near the top. Using a sharp knife, cut downward, removing corn from the cob at about two-thirds the depth of the kernels. Continue until all of the corn is removed.
When cauliflower is done, remove from oven and let cool slightly. In a medium bowl, toss cauliflower with corn and cucumber. Drizzle with tahini dressing, sprinkle with minced basil and serve.