Cook orzo in salted water until just its just about done. Add the spinach to the pot and stir it around so that it wilts. Cook for a minute or so and drain into a large bowl.
Toss with lemon juice, zest, olive oil, garlic, onion and feta cheese. Sprinkle with freshly roasted almonds. Give everything a good grind of black pepper. You probably wont need salt because of the feta, but adjust seasonings to your taste.