Add all ingredients to large freezer bag. Mix gently to combine. Remove excess air, seal and freeze.
Cooking instructions:
Thaw.
Slow cooker on low for 4-6 hours.
Instant pot: Pressure cook on high for 60 minutes for a 3 pound roast. Add or subtract 20 minutes of cook time for every additional pound of beef. Shred.
Serve on small soft shell tacos with Sriracha mayo, minced purple onion, kimchi, and cilantro.