Cowboy butter is the whole sauce: four tablespoons of butter with garlic, Dijon, lemon juice, smoked paprika, chilli flakes and parsley. There is no cream and no cheese sauce.
The steak comes out first and rests while that butter is made. Three minutes is exactly what the safety standard asks for, so the recipe's timing and its doneness rule are the same thing.
Why This Recipe Works
- Searing one-inch cubes over high heat browns them before the interior passes 145 degrees Fahrenheit.
- Resting on a plate lets the temperature even out while the pan is used for the butter.
- Dijon emulsifies the butter with the lemon juice so the sauce clings rather than splitting into fat.
- A third of a cup of pasta water is what turns melted butter into a glossy sauce.
Ingredient Notes
- Sirloin steak
- A pound in 1-inch cubes, seared to at least 145 degrees Fahrenheit and rested three minutes.
- The cowboy butter
- Four tablespoons of butter with garlic, Dijon, lemon juice, smoked paprika, chilli flakes and parsley. That is the entire sauce.
- Refrigerated cheese tortellini
- Eighteen ounces, cooked to its own package timing.
How to Make It
Sear and rest
Season steak. Sear in oil over high heat until browned and at least 145 degrees Fahrenheit, then rest 3 minutes on a plate.
Make the cowboy butter
Reduce heat and melt butter. Add garlic, Dijon, lemon juice, paprika, red pepper flakes and parsley.
Cook the tortellini
Cook tortellini according to package directions; reserve 1/3 cup pasta water and drain.
Toss to a glossy sauce
Toss tortellini in cowboy butter, adding pasta water to make a glossy herb sauce.
Steak back in, briefly
Return steak cubes just long enough to coat. Do not add provolone, bell pepper or onion.
145F, Then Three Minutes
Whole-muscle beef has a two-part standard: a temperature and a hold. This recipe treats the hold as working time rather than dead time.
- Cut for the sear1 lb of sirloin in 1-inch cubes, seasoned with 1 tsp salt and 1/2 tsp pepper. Cubes that size brown on the outside before the middle overshoots.
- High heat, one panSeared in 1 tbsp of neutral oil over high heat. The same pan carries the whole recipe, so the fond from this stage ends up in the butter.
Check before you continue
At least 145F, then a 3-minute rest — Instant-read thermometer, into a cube
Both halves count. 145F is the reading; the three minutes at that temperature is what completes the standard for whole-muscle beef. The recipe spends that window making the cowboy butter in the same pan, so nothing waits idle and the steak is not being held over heat while it rests.
- Back in for seconds onlyThe cubes return at the very end, just long enough to coat in the butter and pasta water. They are already at temperature; any real time back on the heat would take them past it.
- And nothing elseNo provolone, no bell pepper, no onion. Those belong to a cheesesteak tortellini, and adding them here would make it a different dish.
Success Tips
- Get the pan properly hot before the cubes go in — a cool pan grey-steams them instead of searing.
- Use the rest to make the butter; the timing is designed to overlap.
- Return the steak for seconds, not minutes. It is already at temperature.
Serving Ideas
Four servings on plates, the tortellini glossy with cowboy butter and the browned steak cubes through it, parsley and chilli flecks over the top.
Frequently Asked Questions
Why rest the steak for three minutes?
145 degrees Fahrenheit with a three-minute rest is the safety standard for whole-muscle beef, and the rest is part of it.
Can I add provolone or peppers?
No. The recipe says not to.
Is there cream in the sauce?
No. It is butter, aromatics and a third of a cup of pasta water.
