In medium bowl stir together oil, tarragon, salt and pepper. Add tomatoes and shallots, toss to coat. use slotted spoon to remove tomatoes and shallots to another bowl, reserving olive oil mixture.
Place chicken in shallow roasting pan. Brush chicken with reserved olive oil mixture.
Roast in oven for 20 minutes.
Add shallots to pan and continue roasting 15 more minutes.
Add tomatoes and roast 10-12 more minutes until chicken is tender and no longer pink. (Bone in thighs usually take 45 minutes total)