01 - If using wooden skewers, submerge them in water for at least 20 minutes to prevent burning during grilling.
02 - Set the grill to medium-high heat, targeting approximately 400°F. Allow the grates to fully heat before placing skewers.
03 - In a small saucepan over low heat, melt the butter. Add the minced garlic and cook for 1 minute until fragrant. Remove from heat and stir in the chopped parsley, lemon zest, salt, and black pepper.
04 - Thread zucchini rounds, bell pepper pieces, and red onion chunks alternately onto each skewer, distributing the vegetables evenly.
05 - Using a basting brush, coat the assembled skewers generously with half of the prepared garlic butter mixture.
06 - Place the skewers directly on the grill grates. Cook for 3 to 5 minutes per side, turning occasionally, until the vegetables are tender with light char marks throughout.
07 - Remove the skewers from the grill and immediately brush with the remaining garlic butter while still hot.
08 - Arrange the skewers on a serving platter alongside lemon wedges. Serve warm.