ingredients in a mixing bowl. Season to taste, then cover and refrigerate 30 minutes prior to serving.
1. Toss shrimp with cumin, coriander, chili powder, salt, lime (zest and juice), lemon and orange juice, and scallion in a bowl. Cover and refrigerate 20 minutes or until ready to serve.
2. Divide and spread guacamole over toasted tostadas. Top with coleslaw and marinated shrimp, then garnish with cilantro and radish. Place tostadas on plates and serve.
Tip: To toast tostadas, preheat oven to 400°F. Brush both sides of tortillas with olive oil and bake on a foil-lined baking sheet until crisp.