Preheat the oven to 425 degrees F.
In a large bowl, coarsely mash half the avocado. Add the turkey, egg, almond flour, cilantro, olive oil, smoked paprika, chili powder and salt together until just fully combined.
Gather the thawed spinach in a dish towel an squeeze out all the moisture. Add the bowl with the turkey mixture. With clean hands, mix the ingredients until the turkey is nicely distributed but not overly worked.
Form the turkey mixture into 8 small burgers – an ice cream scoop or wet hands helps – and arrange on a parchment-lined baking sheet evenly spaced. Pat the balls and form into patties on the sheet. The mixture will be quite wet, but it will hold together in the oven!
Drizzle the burgers lightly with olive oil or give them a spritz of cooking spray. Transfer to the oven until cooked through, about 15 minutes. Flip the burgers and cook for another 5-10 minutes on the second side until lightly browned.
Serve the burgers on toasted buns or “naked” as lettuce wraps with a dollop of smoky herbed mayo (see note), one thin slice of the remaining avocado half, and a few arugula leaves.