Stew:

In a heavy Dutch oven, melt butter over moderately high heat until the foam subsides and in it brown the chuck, patted dry and seasoned with salt and pepper. Work in batches as needed, removing the beef to a plate as it is browned. Add the additional butter and the onions, turn down the heat to low and cook, stirring as necessary, bringing up any browned bits from the bottom of the pan until softened, about 8 to 10 minutes. If at any point it looks as if the onions or the bottom of the pan is burning, add a little water, about a tablespoon at a time, scraping the bottom of the pan.

Add in the garlic and cook for a minute or two longer, stirring, until fragrant. Add the thyme, the sage, the bay leaf, the broth, and the Guinness stout, bring the liquid to a boil and simmer the mixture, covered, stirring occasionally, for about 2 to 2 1/2 hours, or until the meat is tender.

Discard the bay leaf, and whisk in bits of the beurre manie, whisking until the sauce is thickened. Taste and adjust salt and pepper, add the jelly or brown sugar to taste. Serve over baked or mashed potatoes, garnished with parsley.

For Buerre Manie:

In a small cup, mix butter and flour together; if needed, scrape out and knead it together with fingertips, being careful to not overheat the butter.