Gather all ingredients before starting the recipe.
Pre-heat oven to 375°F
Grate the zest from 1 whole lemon , finely slice 2 cloves garlic and trim and slice 1 whole fennel bulb  into 1/2" slices. Set aside until ready to use.
 Spray the bottom of a medium sauté pan with vegetable oil spray and heat the pan over medium high heat for 2-3 minutes.
Season 2 chicken breasts  on both side with  kosher salt and freshly ground black pepper When the pan is hot, add the chicken, skin side down, and sear for 6-8 minutes per side or until golden brown. Remove chicken to a platter and reserve.
Place fennel in the same pan and sauté for 2-3 minutes per side, or until nicely golden.
 Remove fennel to a casserole dish and top with the reserved chicken.
 Add 1 tbsp unsalted butter  to the pan and when the butter has melted, add 8-10 sprigs fresh tarragon ,  the lemon zest and sliced garlic and stir to combine.
 Cook for one minute and then de-glaze the pan with 1/2 cup white wine . Stir and scrape up all the brown bits from the bottom of the and cook until the wine has reduced by half.
 Add 1/2 cup chicken stock , stir to combine, then pour the juices over the reserved chicken and fennel.
 Place pan into a pre heated oven and roast for 25-30 minutes or until the pan juices have been reduced by half and the chicken is cooked through and the fennel is tender and nicely browned.
Serve with sliced lemon wedges.