Heat oil and butter in a large Dutch oven set over medium heat.
Brown half of the stew meat, and transfer it to a paper towel-lined plate. Add the remaining meat to the Dutch oven, brown all sides, and place it with the other browned meat.
Place the chopped onions in the pot and cook 3-4 minutes or until translucent and softened. Add the garlic and cook 30 seconds, stirring often.
Slowly add the beer and stir while deglazing the pan.
Add the browned beef and all other ingredients EXCEPT carrots, potatoes and parsley. Stir well.
Bring the mixture to a boil, stir, cover and reduce the heat to low.
Simmer the stew (covered) for 1 hour.
Remove the lid and simmer an additional 1 hour.
Add carrots and potatoes and cook until vegetables are tender and stew has thickened.
The stew should be somewhat thick(ish). If too thick, add additional water or broth. If it is too thin, add 1-2 tablespoons cornstarch (according to package directions). Simmer until the stew has thickened to the desired consistency.
Garnish with chopped parsley and serve with toasty bread.