T-bone steak

• Longissimus lumborum (sirloin)

  Loin · low use · connective tissue: low

  The continuation of the same back muscle behind the ribs. It is the same anatomy the rib eye comes from, which is why 'where does the rib eye stop and the sirloin start' is a butchery question rather than an anatomical one — and why the systems answer it differently.

  Muscles: Longissimus lumborum

• Psoas major (fillet)

  Loin · low use · connective tissue: low

  A muscle that runs inside the ribcage along the spine and does almost no work, which is the whole explanation for the fillet: barely used means barely any connective tissue and barely any marbling, so it is the tenderest cut on the animal and the one with the least fat to protect it from a fire.

  Muscles: Psoas major, Psoas minor, Iliacus

Named the way uk butchery names it. If the counter does not recognise the name, the anatomy is the fallback: ask for the cut by where it comes from.

What to say

T-bone steak.

If that draws a blank

Ask for loin or loin — the muscle is Longissimus lumborum.

What to specify

Thickness, which governs the timing more than weight does — the usual range is 30–50 mm. Typical weight is 400–900 g.

Derived from how hard the muscle works and how much connective tissue it carries, which is the pairing that decides whether a cut wants a fire under it or beside it. BBQHQ does not rank cuts and does not name a best one.

• Low connective tissue: there is nothing here that a long cook would improve. Direct or two-zone heat, taken off at a doneness rather than at a texture, and every extra minute past that point costs moisture.
• A supporting muscle that does little work, so it is tender to begin with and has nothing to gain from time.
• Low connective tissue: there is nothing here that a long cook would improve. Direct or two-zone heat, taken off at a doneness rather than at a texture, and every extra minute past that point costs moisture.
• A supporting muscle that does little work, so it is tender to begin with and has nothing to gain from time.

BBQHQ holds cooking evidence for this cut as t-bone steak.

BBQHQ has established no substitute for this cut. That is a statement about what has been checked rather than a claim that none exists.

BBQHQ has not established how this cut maps to other butchery systems.

The UK side of these mappings rests on AHDB’s published cutting specifications, which BBQHQ has read. The US side does not: USDA’s Institutional Meat Purchase Specifications and the Beef Checkoff cut pages both refuse automated access, so no mapping here reaches “same cut” across two butchery systems. See the open question.

400–900 g