1-First, cut the meat into 1-inch cubes, keeping the marbled fat for flavor while discarding large fat pieces. Season the beef with black pepper, garlic salt, celery salt, and toss it with flour for a nice coating.

2-Next, heat olive oil in a skillet and sear the meat in batches for 45 seconds per side to add color and depth. Transfer it to the slow cooker once done. In the same skillet, melt 1 tablespoon butter and cook onions for 5 minutes, then add garlic for 1 minute and deglaze with a splash of red wine.

3-Transfer the onion mixture to the slow cooker and add the rest of the ingredients except peas, cornstarch mixture, and the remaining butter. Cook on low for 7 ½ to 8 hours or on high for 3 ½ to 4 hours until everything is tender.

4-About 15 minutes before serving, stir in the peas. Remove bay leaves and rosemary sprig. If you want a thicker stew, add the cold water-cornstarch mix and let it thicken. Finish by swirling in the remaining 2 tablespoons of cold butter for a smooth texture, and add a few drops of browning sauce if desired.