Pat the beef chuck cubes dry with paper towels and season generously with salt and pepper.
Heat the olive oil in a large skillet over medium-high heat. Add the beef in batches, making sure not to crowd the pan, and sear each side until browned, about 3-4 minutes per side.
In the same skillet, add the chopped onion and minced garlic. Sauté until fragrant and translucent, about 3 minutes.
Stir in the tomato paste and cook for an additional minute to bring out its rich, concentrated flavor.
Transfer the seared beef and sautéed aromatics to your slow cooker.
Add the sliced carrots, dried thyme, dried rosemary, bay leaves, and beef broth. Give everything a gentle stir to combine.
Cover and cook on low for 7-8 hours or on high for 4-5 hours until the beef is tender and flavors meld.
About 30 minutes before serving, stir in the frozen peas. They will thaw and cook quickly.
Taste the stew and adjust salt and pepper as needed.
Discard the bay leaves before serving. Ladle into bowls and enjoy with crusty bread or mashed potatoes if desired.