Toss the sweet potatoes, brussels sprouts, and cauliflower in 1 tablespoon oil, ½ teaspoon salt, ½ teaspoon garlic granules, and ¼ teaspoon pepper. Transfer to a baking sheet and roast in the oven for 30 minutes.
Meanwhile, toss the bread cubes with 1 tablespoon oil, ½ teaspoon salt, and ½ teaspoon garlic granules. Lay in a single layer on another baking sheet and bake for 12 minutes until browned.
In a small bowl, add all the remaining olive oil, salt, garlic granules, and pepper. Mix in the vinegar, maple syrup, and grainy mustard.
Add the spring greens to a large bowl. Place the roasted vegetables on top, then drizzle with the dressing and toss. Add the toasted bread and pomegranate seeds, and serve.