Preheat oven to 400ºF.,Place cauliflower and corn in a bowl and toss together with olive oil and salt and pepper.,Place seasoned veggie mixture onto a sheet pan and roast 30 to 40 minutes or until veggies have some color. Allow to cool slightly.,Place cauliflower mixture into a serving dish and add feta cheese, basil and mustard.,Toss to combine and season as needed to taste.