Combine all ingredients and whisk, or use an immersion blender, until smooth. Refrigerate for one hour to allow flavors to meld.
Heat cast iron griddle to med high heat.Combine zucchini, yellow squash and onion. Drizzle lightly with olive oil. Toss to coat. Grill until al dente.Remove from griddle to a large bowl. Cool slightly. If using larger squash, further cut pieces into bite size chunks (large dice). Add tomatoes and herbs and toss. Add cumin dressing, toss to coat.
Portion salad for your guests, top with crumbled cotija and season with fresh cracked black pepper. Salad can be served either at room temperature or chilled.
Keyword things to do with zucchini, zucchini recipes, zucchini salad recipes