Heat butter over medium low heat in a heavy ovenproof skillet. Add the onions cook for 20 minutes or so, stirring occasionally. When the onions are a deep golden color, remove from the pan and set aside.
Chicken Thighs
Preheat oven to 350 F.
Combine the flour, salt, chili powder, thyme, allspice, & black pepper. Dredge each piece of chicken in the flour mixture, shaking off the excess.
In the same pan as the onions, heat the oil over medium high heat. Add each piece of chicken & fry for a few minutes until golden brown; flip & cook for a few more minutes. Transfer to a plate (it will not be fully cooked at this point, just browned – it will finish cooking in the oven).
Turn the heat down & let the oil cool off a little bit. Add the wine – this will definitely bubble & sizzle! Add the broth & simmer until the mixture is thickened slightly. Add the onions & chicken to the pan. Bake for about 20 minutes.
Remove from the oven, add the grapes, baste with the sauce & bake for another 5-10 minutes. Garnish with parsley and serve.
Recipe Notes
To make without using wine:
Use 3/4 cup chicken broth (instead of the 1/3 cup wine & 1/4 cup broth). Add remaining flour (leftover from dredging chicken).
Make a roux with excess oil in skillet & dredging flour.
Add chicken broth & cook until a sauce forms.
Add the onions & chicken to the pan & bake as directed above.