Preheat the oven to 375°F (190°C).
In a pot or casserole, arrange the onions at the bottom, followed by the short ribs, vegetables, and garlic. Sprinkle salt and black pepper, then pour the sauce over everything. Sprinkle thyme and rosemary, and cover with a lid.
Rinse the wheat thoroughly in a sieve and transfer to a bowl with beans, chickpeas, sweet potato, and sauce.
Transfer to a pot or casserole, cover with damp parchment paper, and cover the pot.
Place the two pots in the oven and bake for 40 minutes, then Switch to the convection setting for 3 1⁄2 to 4 hours at 320°F (160°C). Check both pots during cooking, and if more liquid is needed, you can add ¼ to ½ cup of water.
Remove the cover and bake for an additional 30 minutes at 375°F (190°C) for browning the top.