Preheat your oven to 400°F. Line a large 20″x14″ baking sheet (or use 2 smaller 14″ x 9″ baking sheets) with parchment paper. Set aside.
In a large bowl, toss 1 ½ lbs halved baby red potatoes and 1 lb peeled and cut carrots with 2 ½ Tbsp olive oil, 1 Tbsp minced fresh thyme, 2 Tbsp minced fresh rosemary, ½ tsp salt, and ¼ tsp ground black pepper.
Spread the potato and carrot mixture in a single layer on the baking sheet. Place in the oven to roast for about 20 minutes, tossing halfway through.
While the potatoes and carrots are roasting, toss 12 oz trimmed and halved green beans with the remaining ½ Tbsp olive oil, 2 Tbsp minced garlic and ½ tsp salt.
After the carrots and potatoes have roasted 20 minutes, remove the baking sheet from the oven and push them up to to the top of the pan with a spatula. Now add the green beans and spread them into a row.
Place the baking sheet back in the oven to roast for another 25-30 minutes, or until all the vegetables are tender when poked with a fork and some edges are golden brown. Now it’s ready to serve!