1Cut brisket into 3 to 4 large pieces. Place brisket, onion, garlic, tomatoes, bay leaves, salt, cumin, oregano and black pepper in large saucepan. Pour stock over top. Bring to boil on medium-high heat. Reduce heat; simmer 3 hours or until meat is fork-tender. Remove meat from saucepan using tongs or slotted spoon; cut into small bite-size pieces. Set aside.
2Add chilies to saucepan. Simmer 5 minutes or until chilies are softened. Remove bay leaves. Carefully transfer sauce mixture to blender container; cover. Blend on HIGH until smooth. Return sauce mixture to saucepan; add beef and mix to coat well.
3Spoon about 1/2 cup Carne con Chile mixture down lower third of tortillas and roll into burritos. Serve with beans, rice and salsa, if desired.