Preheat an oven to 375 degrees. Heat a few tbsp of olive oil in a deep sided pan over medium high heat. Season chicken on both sides with salt and pepper and sear in the pan until browned on both sides, about 4-6 minutes per side.

While the chicken is searing, mix the veggies on a sheet pan and toss with olive or avocado oil, and salt and pepper, to taste. Pop these in the oven to start roasting while the chicken finished browning, about 10 minutes.

When the chicken is seared on both sided, place the breasts on the sheet tray with the veggies, add 1/4 cup chicken to stock to the sheet pan, and roast until the veggies are fork tender and the chicken is cooked through, 20-22 minutes.

While the meat and veggies roast, make the gravy by first reducing the heat under the pan to medium low and melting the butter. When the butter has melted, add the flour and whisk quickly to incorporate. When the butter and flour have formed a smooth paste, add the stock, half at a time, and whisk to incorporate. Bring the gravy to a simmer and add the sage and the rosemary sprigs as well as additional salt and pepper, if desired. Simmer the gravy on low until time to serve. If gravy is too thick, add more stock, 1/4 cup at a time, until you achieve the desired thickness.

Before serving, add the cream to the gravy and whisk to combine.