In a small jar or bowl, combine lime juice, maple syrup, olive oil, chopped cilantro, garlic powder, salt, and pepper. Whisk until smooth, or shake the jar with the lid on. The fresh lime flavor makes the dressing vibrant and refreshing.
Dice your mango, cucumber, and avocado, and mince the red onion. Let the onion sit for 15 minutes to mellow its sharpness. Toast the walnuts in a dry pan until golden brown to enhance their nutty aroma.
Place arugula in a large mixing bowl, then add mango, cucumber, avocado, blueberries, walnuts, and cilantro. Drizzle with the vinaigrette and gently toss to coat everything evenly. Serve immediately for the freshest flavors.