Add the blended sauce into the pot, and stir, scraping all the browned bits off the bottom of the pot. Cover and simmer over medium-low heat until the meat is very tender, about 2 ½ hours.

White pot on induction cooktop with simmering beef in chili sauce — Jake Sternquist / Food Styling: Holly Dreesman / Prop Styling: Gabriel Greco

Remove the meat from the sauce and allow to cool enough to shred. Shred the meat with your hands or with 2 forks. Stir in about 1/4 cup of the sauce. Blend the diced tomatoes until very smooth and add to the sauce.