Bring a medium pot of heavily salted water to a boil. Add the quinoa and cook until tender, 8 to 10 minutes; drain and let cool.
Meanwhile, preheat a grill to medium high. Drizzle the zucchini and red onions with enough olive oil to coat, season with salt and pepper and toss. Grill the vegetables until well-marked and slightly soft, 3 to 4 minutes per side. Let cool, then chop and transfer to a large bowl.
Add the quinoa and basil leaves to the bowl and toss to combine. Whisk 1/4 cup olive oil, the lemon juice and habanero oil in a small bowl until emulsified (or combine in a blender); season with salt and pepper. Drizzle over the quinoa salad just before serving.