Preheat the oven to 400 degrees F. Spray a baking sheet with non-stick cooking spray and set aside.
Trim the ends off the asparagus. Add to the baking sheet, along with the cauliflower and radishes. Drizzle with olive oil, sprinkle with lemon pepper seasoning and stir to coat. Roast in the oven for 20 - 25 minutes, until lightly browned and softened. Flip halfway through to ensure even cooking.
While the veggies are cooking, whisk together the dressing ingredients. Add water, one tablespoon at a time, as needed to thin the sauce. Once you get a drizzlable texture, you're good.
When veggies are done roasting, assemble the bowls. Divide all the ingredients evenly between four bowls. Top with the sauce and some sliced avocado.