Thinly slice the onion and dice the chorizo.
Heat a heavy-based casserole dish, and add the onion and chorizo. Cook them on a low heat until the sausage releases its fat and the onion is softened.
In the meantime chop the garlic, slice the carrots and red pepper. Halve the potatoes. Add the veggies to the pan when the onion is soft. Put the lid on and steam for a couple of minutes.
Using a sharp pair of scissors , cut down one side of the backbone and open up the poussin. Press it down so it fans out a bit. Rub salt and pepper all over it, then put it in the middle of the pan and sear on both sides.
Add the wine, let it bubble for a couple of minutes then add the chopped tomatoes. If the sauce is too thick just add some water.
Add the herbs, bring to the boil, put the lid on and simmer on low heat for about 30 minutes.
Add the beans, turn the heat up to medium and cook for another 5-10 minutes.
When the sauce is thick, the poussin cooked through and the vegetables are tender - it's ready. Remove the sprigs of the herb and serve with chopped parsley or coriander scattered on top. You'll also want some crusty bread to dunk in the yummy gravy!