In a large pot over medium heat, add the olive oil. Once heated, add diced onion and sauté until translucent, about 5 minutes.
Stir in the minced garlic, diced carrots, and celery. Cook for another 5-7 minutes, stirring occasionally, until the vegetables begin to soften.
Add the shredded rotisserie chicken to the pot, followed by the chicken broth, frozen peas, thyme, rosemary, salt, and pepper. Bring to a simmer and cook for 10 minutes.
In a separate bowl, whisk together the heavy cream and flour until smooth. Slowly add this mixture to the pot, stirring constantly to avoid lumps. Allow the soup to simmer for an additional 5 minutes until it thickens slightly.
While the soup is simmering, prepare the biscuit dough or pastry according to package instructions. Cut into small rounds if using biscuit dough.
Gently drop the biscuit rounds on top of the soup. Cover and cook for 10 minutes until the biscuits are cooked through and fluffy.
Once the soup is ready, serve hot in bowls, garnished with fresh herbs if desired.