Preheat the oven to 375 ℉. Heat oil in a large pot or Dutch oven on the stove over medium heat. Add onion, garlic, 1 teaspoon salt and ½ teaspoon black pepper, or to your liking. Saute for a couple minutes until the onions soften.
3 tbsps olive oil, ½ yellow onion, 3 cloves garlic, 1 teaspoon kosher salt, ½ teaspoon fresh ground black pepper
Add the carrots, potatoes, rosemary and thyme. Cook another 2-3 minutes, allowing the vegetables to begin to cook and the herbs to become fragrant. Add the chicken breasts, whole, and the chicken broth to the pot. Cover and bring to a boil. Once the broth is boiling, lower heat to simmer and cook on medium-low heat for about 25 minutes, stirring occasionally. Make the puff pastry toppers while the soup simmers.
4 medium carrots, 2 medium Yukon potatoes, ¾ teaspoon dried rosemary, ¾ teaspoon dried thyme, 2 chicken breasts, 6 cups chicken broth