Ingredients

• 4 tablespoons olive oil plus more for slate
• 2 2-2 1/2"-thick porterhouse steaks (about 4 pounds total), room temperature
• 1/4 cup herbes de Provence
• Kosher salt, freshly ground pepper
• 3 small Italian eggplants (about 1 1/2 pounds), halved lengthwise
• 6 small beefsteak tomatoes (about 2 pounds), halved crosswise
• 3 small zucchini (about 1 pound), halved lengthwise
• 3 portobello mushrooms (about 1 pound), stems removed
• 2 large red bell peppers (about 1 pound), cut lengthwise into 1 1/2" strips
• 6 garlic cloves, thinly sliced
• 1/3 cup fresh rosemary leaves
• 1/2 cup olive oil
• Kosher salt, freshly ground pepper
• 1 medium round loaf sourdough bread (about 1 1/2 pounds), cut into 1" wedges
• 1/4 cup olive oil
• 1 garlic clove, halved
• Kosher salt
• Special equipment: A few 16x16" untreated natural slate floor tiles 1/4-1/3" thick (in case one breaks)

Instructions

1. If using a charcoal grill, prepare for high heat. Place slate on grill grates and heat (don't worry if it splits or cracks; it can still be used). If using a gas grill, place slate on grates, then heat grill to high (cover grill while heating and grilling). Using paper towels and long-handled tongs, lightly coat slate with oil.
2. Sprinkle steaks with herbes de Provence and season with salt and pepper, pressing gently to adhere. Drizzle each steak with 2 tablespoons oil to moisten herbs. Grill on hot slate until an instant-read thermometer inserted into the thickest part registers 115°F for medium-rare (the temperature will continue to rise as steaks rest), 10-15 minutes per side.
3. Transfer to a cutting board or platter and let rest 20 minutes before slicing.
4. For vegetables: If using a charcoal grill, coals should have cooled to medium heat. If using a gas grill, reduce heat to medium high. Cut a small strip from rounded side of eggplant halves so they will lie flat. Combine eggplants, tomatoes, zucchini, mushrooms, bell peppers, garlic, and rosemary on a rimmed baking sheet; drizzle with oil, season with salt and black pepper, and toss to coat. Place vegetables on slate and grill until browned and tender, 5-8 minutes per side. (Some vegetables may cook faster than others.) Transfer to a platter.
5. If using a charcoal grill, coals should have cooled to medium heat. If using a gas grill, reduce heat to medium high.
6. Cut a small strip from rounded side of eggplant halves so they will lie flat. Combine eggplants, tomatoes, zucchini, mushrooms, bell peppers, garlic, and rosemary on a rimmed baking sheet; drizzle with oil, season with salt and black pepper, and toss to coat. Place vegetables on slate and grill until browned and tender, 5-8 minutes per side. (Some vegetables may cook faster than others.) Transfer to a platter.
7. For bread and assembly: If using a charcoal grill, coals should still be around medium heat. If using a gas grill, keep heat at medium-high. Drizzle both sides of each slice of bread with oil. Place bread on slate and grill until golden brown, about 2 minutes per side. Transfer to a serving board or plate, rub both sides of bread with garlic, and season with salt. Serve steaks with grilled vegetables and bread alongside.
8. If using a charcoal grill, coals should still be around medium heat. If using a gas grill, keep heat at medium-high.
9. Drizzle both sides of each slice of bread with oil. Place bread on slate and grill until golden brown, about 2 minutes per side. Transfer to a serving board or plate, rub both sides of bread with garlic, and season with salt.
10. Serve steaks with grilled vegetables and bread alongside.