Cooking steak at home shouldn't be intimidating. For this salad, we want a medium-rare to medium finish so the meat stays tender when eaten cold or room temperature.

1. Prepare the Beef: Pat your sirloin dry with paper towels. Moisture is the enemy of a good sear. Season it aggressively with sea salt and cracked black pepper on both sides.
2. The Sear: Get your pan—preferably cast iron—smoking hot. Add a tiny splash of oil. Lay the steak down. Let it sear for 3–4 minutes without moving it. You want a deep, mahogany brown crust. Flip it once and cook for another 3 minutes.
3. The Rest: Transfer the beef to a cutting board. This is non-negotiable. Let it sit for 5 to 7 minutes. This allows the internal fibers to relax and reabsorb the juices.
4. Whisk and Assemble: While the meat rests, combine the olive oil, lime juice, and a pinch of salt in a small bowl. Toss your greens lightly in the dressing. Top with the tomatoes, onion, and sliced beef. Finally, fan your avocado slices over the top.

This salad is a meal-prep champion if you respect the ingredients. If you are packing this for work, keep the components separate.

Store your sliced, cooked steak in an airtight container in the fridge for up to three days. Keep the dressed greens separate; if you dress them too early, the acidity of the lime juice will wilt the arugula into a mushy state. Slice your avocado fresh right before you sit down to eat to prevent browning. If you must slice it ahead, a heavy squeeze of lime juice over the slices will slow the oxidation process.