Preheat the oven to 400°F.
Prepare the veggies: On a baking sheet lined with parchment paper, combine the chopped cauliflower and edamame. Drizzle with olive oil and sprinkle with cumin, paprika, red pepper chili flakes, coriander, garlic powder, salt, and pepper. Toss to coat evenly.
Place the baking sheet in the oven and roast for 45 minutes, or until crispy, turning the veggies halfway through cooking.
While the veggies are roasting, use a large mixing bowl to combine all salad ingredients. Taste to adjust seasoning and toss to mix well.
To assemble the bowls, spread a generous dollop of vegan tzatziki across the bottom of each serving bowl. Layer the roasted veggies and salad on top. Top each bowl with a handful of pistachios for extra crunch, followed by chopped dill and a drizzle of additional tzatziki sauce.