Heat a lightly oiled skillet over med-high; pat meat dry, trim excess fat + cut into ½-inch pieces; season beef with salt/pep + sear undisturbed 2-3 min until browned; flip meat over + sear 2-3 min more for medium-rare (for more well done, increase cook time 1-2 min per side)

Meanwhile, slice tomatoes in half; mix half the seasoning blend with 2 tbsp water, 2 tsp oil + salt/pep; whisk to combine

Add spinach to a large bowl; add beef, tomatoes + dressing; toss to combine

Divide salad onto 2 plates + sprinkle each with 1-2 tbsp cheese