Preheat the oven to 200 °. Salt and pepper the guinea fowl legs and fry them with a little oil in a roaster until golden brown and remove. Sauté the finely diced onion in it, deglaze with the white wine and simmer a little. Add the tomatoes, sugar, poultry stock and spices. Place the guinea fowl legs on top and let simmer in the oven for about 35 - 40 minutes.
Remove the guinea fowl legs and keep warm. Fish the juniper berries, bay leaf and garlic cloves out of the sauce. If the sauce is still too thin, reduce it a little and season well with salt and pepper. Whip the cream (should not be stiff) and fold into the tomato sauce with the gin. Serve with the chicken legs.