Add the cubed beef to a large bowl and toss with the flour until evenly coated.
In a large cast-iron skillet over medium-high heat, add the olive oil and heat until shimmering.
Carefully add the floured beef to the hot skillet and brown on all sides, about 4 to 6 minutes. Work in batches if needed to avoid overcrowding.
Transfer the browned beef to the insert of a slow cooker.
To the slow cooker, add the chopped celery, sliced carrots, frozen peas, cubed potatoes, chopped onion, and minced garlic.
Add the bay leaves, dried thyme, chopped parsley, tomato paste, kosher salt, and black pepper.
Pour in the beef broth and red wine. Stir gently to combine all the ingredients.
Cover and cook on low for 8 hours or on high for 3 to 3 ½ hours, until the potatoes and beef are tender.
Before serving, remove and discard the bay leaves. Taste and adjust seasoning with additional salt and pepper if needed.