Preheat oven to 375 degrees F. and line a large baking sheet with parchment paper or a silpat liner.
Place all of your cut vegetables onto prepared baking sheet, use 2 if necessary. Bake for 20 minutes, or until slightly softened. Vegetables will cook more in the slow cooker.
Place beef into large ziploc with flour, salt and pepper. Shake to coat all pieces.
Heat large dutch oven over medium heat with bacon drippings (preferred) or olive oil.
Brown flour coated beef pieces in hot pan to brown both sides, about 5 minutes per side.
Transfer browned beef to slow cooker placed on low setting. Add roasted vegetables and broth.
Melt butter into a medium saucepan over medium heat. Whisk in flour, salt and pepper until smooth.
Slowly whisk in broth. Continue whisking until thickened. Stir in dried thyme then stir into slow cooker. Let cook for 5-8 hours until beef is fork tender.
Season to your liking. Serve warm over mashed potatoes or just by itself in a bowl.