Microwave 2 potatoes on high, 6-8 min, flipping over halfway through cook time (caution, that's a hot potato!); carefully cut in half, then set aside

Meanwhile, pat tuna steaks dry with paper towels, season generously with salt + seasoning pack; heat 1 tbsp oil in skillet over med-high; sear fish 2 min per side for med-rare* (if width of steak is less than 1" reduce by 1 min on one side)

Heat 1 tbsp oil in large skillet over med-high + sauté half the spinach + salt/pep 1-2 min until wilted; add remaining spinach + cook 1-2 min more until all spinach is wilted

Divide ingredients to 2 plates