In a dutch oven cook bacon over a medium high heat until desired crispness, remove and set aside

Season beef with salt and pepper

Add olive oil to dutch oven and brown the beef, remove and set aside

Add butter and onions, cook until onions are soft and translucent, 2-3 minutes

Add in flour and whisk to make a roux, cook for 1 minute

Pour in Guinness and whisk until there are no more lumps

Add tomato paste, chicken stock, carrots or parsnips, worcestershire sauce, celery, bay leaves and thyme, stir to combine

Return beef, potatoes and bacon to the pot

Bring to a boil, then reduce to low, cover and simmer for up to 2 hours, or until sauce has thickened to a loose gravy and vegetables are fork tender

Taste and add salt and pepper as needed, remove bay leaves and enjoy