Hearty beef and vegetable casserole bakes tender beef chunks with root vegetables in a savory gravy. This high protein, family-friendly dinner is wholesome, filling, and perfect for cold-weather meals.
Preheat oven to 325°F. Heat olive oil in a large oven-safe pot over medium-high heat until shimmering.
Sear the beef chunks in batches, turning to brown each side deeply, then transfer to a plate and set aside.
Reduce heat to medium and sauté onion, celery, and garlic for 3–4 minutes until softened and aromatic, scraping up any brown bits.
Stir in flour, tomato paste, thyme, and rosemary; cook for 1 minute, then gradually whisk in beef broth to form a smooth gravy.
Add seared beef, carrots, potatoes, peas, salt, and pepper to the pot. Stir to combine and cover tightly with a lid or foil.
Bake in the preheated oven for 90 minutes, stirring halfway. Check for tenderness: beef should be fork-tender and vegetables soft but intact.
Remove from oven. Let rest for 10 minutes before serving to allow juices to settle for optimal flavor and texture.