Preheat oven to 350°F (180°C).

Place chicken breasts in an oven-proof dish.

Sprinkle with chopped garlic, salt, and pepper.

Arrange lemon wedges around the chicken.

In a measuring jug, mix white wine and oil.

Pour wine and oil mixture over the chicken.

Place fresh tarragon sprigs on top of the chicken.

Cover the dish with foil.

Bake for approximately 45 minutes, or until chicken is cooked through.

While the chicken is baking, prepare the sauce.

Melt butter in a pan over medium heat.

Add flour to the melted butter and whisk to form a roux.

Remove the pan from the heat.

Gradually whisk in milk, wine stock from the chicken dish, and cream until smooth.

Return the pan to heat and bring the sauce to a boil, stirring constantly.

Reduce heat to low and simmer for 6-10 minutes, allowing the sauce to thicken.

Remove the sauce from the heat and season with salt and pepper to taste.

Stir in chopped fresh tarragon and brandy.

Whisk until well combined.

Remove chicken from oven.

Arrange the cooked chicken in a serving dish, discarding the used tarragon sprigs and lemon wedges.

Pour the prepared tarragon cream sauce over the chicken.

Garnish with a fresh sprig of tarragon and lemon wedges before serving.