Wash the blood oranges and avocados thoroughly. Slice the blood oranges into thin rounds and catch the juice in a bowl. Halve the avocados, remove the pit, and scoop into bite-sized pieces. Prepare red onion, fresh mint, and greens.

Soak the red onion slices in cold water for about 10 minutes to mellow the flavor. Drain and set aside.

In a bowl, whisk together olive oil, lime juice, and honey or agave syrup. Season with salt and pepper to taste.

In a large salad bowl, layer spinach or arugula, then add blood orange slices, avocado pieces, onion, and mint leaves. Pour over dressing and gently toss.

Plate the salad and garnish with extra mint or dressing if desired. Serve immediately.