1-First: prepare all ingredients as outlined: chop vegetables and cube the beef. This step ensures everything is ready, helping you avoid any rush during cooking.

2-Second: in a large pot, heat the olive oil over medium-high heat. Brown the beef cubes on all sides to lock in flavor, then set them aside. This searing step is key for that rich beef stew flavor.

3-Third: add onions to the pot and cook until soft, stirring as needed. This builds a tasty base for your stew.

4-Fourth: pour in the beef broth and red wine if using, scraping up those browned bits for extra taste.

5-Fifth: return the beef to the pot along with potatoes, carrots, celery, tomato paste, and rosemary. Bring it to a boil, then cover and simmer on low for about 1 hour, or until the beef is tender.

6-Sixth: make a cornstarch slurry by mixing it with water, and add it gradually to thicken the stew. Let it boil for 1-2 minutes to blend well.

7-Finally: stir in the peas and simmer for another 5-10 minutes. Taste and season with salt and pepper as needed. For variations, remember you can swap beef with other proteins at this stage.