In a small mixing bowl, combine the olive oil, mustard, lemon juice, hot sauce, and garlic. Season with salt and pepper. Whisk to blend well.
In a medium mixing bowl, combine the corn, basil, onion, tomatoes, and bell pepper. Add the dressing and toss to mix. Cover and chill for at least 2 hours before serving. Using 3 to 6 spears of asparagus, form a triangle in the center of each serving plate. Spoon the corn and tomato mixture in the center of each plate. Garnish with green onions.