Roasting Method (for deeper flavor and hands-off cooking):

1. Preheat Oven and Prepare Potatoes: Preheat your oven to 400°F (200°C). While the oven is preheating, wash and chop your potatoes into bite-sized pieces, about 1-inch cubes. Evenly sized pieces will ensure they cook at the same rate. You can peel the potatoes if you prefer, but leaving the skin on adds nutrients and texture.
2. Prepare Green Beans and Garlic: Wash and trim the green beans, snapping off the stem ends. If the beans are long, you can cut them in half for easier eating. Peel and mince the garlic cloves. Mincing the garlic finely will allow its flavor to infuse evenly throughout the dish.
3. Combine Ingredients: In a large bowl, combine the chopped potatoes, trimmed green beans, minced garlic, olive oil, Italian herbs, salt, and black pepper (and red pepper flakes, if using). Toss everything together thoroughly to ensure the vegetables are evenly coated with the oil and seasonings. This step is crucial for flavor distribution.
4. Roast the Vegetables: Spread the vegetable mixture in a single layer on a large baking sheet. Avoid overcrowding the pan, as this can steam the vegetables instead of roasting them. If necessary, use two baking sheets. Roast in the preheated oven for 25-30 minutes, or until the potatoes are tender and golden brown, and the green beans are crisp-tender and slightly charred in spots. For even browning, you can toss the vegetables halfway through the roasting time.
5. Serve: Once the vegetables are roasted to perfection, remove them from the oven. Taste and adjust seasoning if needed. Garnish with fresh parsley, if desired, and serve hot with lemon wedges on the side.

Sautéing Method (for quicker cooking and stovetop convenience):

1. Prepare Potatoes: Wash and chop your potatoes into smaller, thinner pieces for faster cooking in a skillet. Think about quartering or slicing them into half-moons, about ¼-inch thick. Smaller pieces will cook more quickly and evenly in the skillet.
2. Par-boil Potatoes (Optional but Recommended): For faster cooking and guaranteed tender potatoes in the skillet, you can par-boil them. Place the chopped potatoes in a pot of salted water, bring to a boil, and cook for 5-7 minutes, until slightly softened but not fully cooked. Drain the potatoes well. This step is optional but highly recommended for ensuring tender potatoes in a shorter cooking time on the stovetop.
3. Sauté Garlic and Potatoes: Heat olive oil in a large skillet over medium-high heat. Add the minced garlic and sauté for about 30 seconds to 1 minute, until fragrant but not browned. Be careful not to burn the garlic, as it will become bitter. Add the potatoes to the skillet and sauté for 10-15 minutes, stirring occasionally, until they are tender and lightly browned. If you par-boiled the potatoes, this step will be faster.
4. Add Green Beans and Seasonings: Add the trimmed green beans to the skillet along with the Italian herbs, salt, and black pepper (and red pepper flakes, if using). Continue to sauté for another 5-7 minutes, or until the green beans are crisp-tender and bright green. Avoid overcooking the green beans, as they will become mushy.
5. Serve: Once the green beans are cooked to your liking, remove the skillet from the heat. Taste and adjust seasoning if needed. Garnish with fresh parsley, if desired, and serve hot with lemon wedges on the side.