Cut olives into 1/4" slices. Cut Roma tomato into 1/2' dice. Mince garlic. Zest and halve lemon. Cut one half into two wedges and juice the other half. Trim ends off green beans. Cut into 1" pieces. Cut potato into 1/2" dice. Rinse trout fillets, pat dry, and season both sides with 1/2 tsp. salt and 1/4 tsp. pepper.

Bring a small pot with potatoes and 2 cups lightly salted water to a boil over high heat. Cook until tender but not falling apart, 5-8 minutes. Add green beans and cook until bright green and tender, 3-4 minutes. Drain in colander and set aside.

In a small mixing bowl, combine tomatoes, half the lemon zest (reserve remaining for garnish), olives, capers, 1 Tbsp. olive oil, 1/4 tsp. salt, and 1/4 tsp pepper. Set aside for flavors to marry.

Place a medium non-stick pan over medium-high heat. Add 1 tsp. olive oil and trout, skin side up, to hot pan. Cook until browned, 3-5 minutes. Flip, reduce heat to medium, and cook until skin is crispy and trout reaches a minimum internal temperature of 145 degrees, 4-6 minutes. Remove pan from burner and set aside. While trout cooks, make salad.

Mix garlic, 1 Tbsp. lemon juice, and 2 Tbsp. olive oil to a large mixing bowl. Add 1/2 tsp. salt, 1/4 tsp. pepper, potatoes, green beans, and spinach to bowl. Toss to coat.

Place salad onto a bowl or shallow plate. Set trout next to salad, skin side down, and top with tomato relish. Garnish to taste with remaining lemon zest and lemon wedges.