Dissolve sugar and oil in a 6 qt. pot, brown it (not too dark, more light brown but dissolved. Don’t use utensils to combine the oil and sugar as the sugar will stick to the utensil, just tilt the pot from right, a few times, to let so the sugar and oil combine without getting burnt. 

Rinse roast, pat dry. Put the salt on both sides. Put the roast in the pot on the dissolved brown sugar and sear it both sides about 10-12 minutes. Remove roast from pot. 

Add the Spanish onions in the pot of sugar (it should be more watery from the roast). Let the onions caramelize in the sugar for about 15-20 minutes. Add portobello mushrooms. Add mustard powder, onion soup mix, black pepper. Add 1 c. water. 

Bake for about 4 hours (30 minutes on 40 and then 3 1/2 hours on 350F. Remove from oven, add the 1/4 c. wine and bake another 10 minutes at 350. Cool a few hours. 

Cut 1/2 inch slices. You can put corn starch in the gravy so when you serve a slice of the French roast you put the gravy on, it adds great taste.