I, too, use boneless chuck roast for my pot roast. All that fat throughout the roast makes for some good eating. Sorry to admit I don't put it through fitness pal or any other tool which will give the nutritional breakdown. However, it's LCHF and tender and delish.

A dutch oven is okay, but a very large, heavy deep skillet with lid will do.
Preheat oven to 250 degrees F.

On stove top put
Oil in the skillet.
When oil is hot, add the beef in one large chunk and sear on all sides until brown. Not too much, as this toughens the surface of the meat. Just enough to carmelize the surface.

Braising meat requires liquid, and I like to make certain the liquid reaches at least to the top of the meat. I tell you this because your roast may be small or large.

Add 1 large can tomato sauce, then some vinegar (I like to use balsamic because of the strong, dark taste). Both the tomato sauce and the vinegar are necessary to break down the connective tissue in the beef. That's what makes the beef tender.

Add salt, pepper remembering that the salt needs to penetrate the meat so a bit extra won't hurt.

When the liquid comes to a boil, cover the skillet or the dutch oven and put it into your preheated oven for at least 2 hours.

This ought to be fork tender. Lastly, adjust the seasoning to your cooking liquid, which can be your sauce.