Season the roast with salt and pepper, then brush with tomato paste.
Heat the oil or clarified butter in a roasting pan and sear the roast on all sides. Then deglaze with 1/4 l red wine and reduce. When the wine is almost reduced, add the cloves of garlic and onions, pour a pinch of sugar over them and fry with them. When they are lightly brown, pour in the stock and the rest of the red wine. I use a lot of wine and broth as we love a lot of sauce. You can also take less here. Add a dash of balsamic vinegar, the sun-dried tomatoes and the sprigs of rosemary.
Place in the oven at 180 degrees in a closed pot for two hours. Check again and again in between and add water or broth if necessary.
Season the sauce to taste and thicken if necessary, remove the rosemary beforehand. I`ve already pureed the sauce. That depends on whether you want pieces in the sauce or not.
This goes well with pasta or white bread and salad or green beans.