Grilled Steak with Blue Cheese, Potatoes, and Broccolini

Ingredients (15)

• + sea salt, or to taste, divided add to pantry
• + 1 teaspoon ground cumin add to pantry
• + 1 teaspoon ground coriander add to pantry
• ✓ 1 teaspoon garlic powder
• + 1 ¼ pounds flat iron steak add to pantry
• + ¾ teaspoon freshly ground black pepper, or to taste, divided add to pantry
• + 2 tablespoons extra-virgin olive oil, divided add to pantry
• + 2 cloves garlic cloves add to pantry
• + 2 russet potatoes, cut into 1/8-inch-thick slices add to pantry
• + 1 bunch broccolini, or more to taste add to pantry
• ✓ sea salt and ground black pepper to taste
• ✓ ¾ cup sour cream
• + 3 ounces crumbled creamy blue cheese add to pantry
• + ½ teaspoon Worcestershire sauce add to pantry
• + 1 lemon, halved add to pantry