In a large skillet, heat the olive oil over medium heat until shimmery. Add the almonds and cook, swirling the pan, until they turn golden brown and fragrant, approximately 2-3 minutes.
Add the zucchini to the pan, tossing to coat with the oil and almonds. Cook for approximately 1 minute, stirring frequently, until the zucchini is just warmed through and crisp-tender.
Transfer the ingredients to a large bowl and toss with 3 tablespoons lemon juice, parsley, salt and pepper. Taste; add more lemon juice, salt and pepper if desired.
Divide among 4 serving plates and top generously with shaved Gruyère. Serve immediately.