Spring Vegetable Sauté

Line a baking sheet with a kitchen towel. Fill a medium bowl with water; add lemon juice. If using baby artichokes, working one at a time, cut away tough outer leaves until only pale-yellow leaves remain. Cut 1/2" off tops; trim stems. Halve artichokes lengthwise, if desired, then remove choke with a spoon. Place in lemon water as you finish. If using globe artichokes, remove stems and all leaves. Scrape out chokes with a spoon; cut each artichoke heart into 4 quarters and add to lemon water. Cook fava beans in a large pot of boiling salted water until just tender, about 2 minutes. Using a slotted spoon, transfer to a bowl of ice water; let cool. Peel and discard outer skins; transfer to prepared baking sheet (if using edamame, boil for only 1 minute; no peeling needed). Repeat cooking process with asparagus and artichokes, returning water to a boil between batches and cooling in ice water before transferring to prepared baking sheet, 3-4 minutes for asparagus and 5-6 minutes for artichokes (1-2 minutes if frozen). Heat 2 tablespoons oil and butter in a large skillet over medium heat; add onion and sauté until translucent, about 5 minutes. Increase heat to medium-high. Add vegetables and cook, stirring occasionally, just until heated through, about 5 minutes. Season to taste with salt, pepper, and more lemon juice, if desired. Transfer vegetables to a serving bowl. Drizzle with oil; garnish with mint and zest.