Heat grill to medium. Once it is hot, clean the grill grate with a wire brush.
Toss the potatoes with 1 tablespoon of the oil and ¼ teaspoon each salt and pepper in the center of a 16-inch square of heavy-duty foil. Fold the foil over and seal the edges to form a packet. Grill the packet, turning occasionally, until the potatoes are tender, 23 to 25 minutes.
Meanwhile, brush the steaks with olive oil and season with ½ teaspoon each salt and pepper. Grill until an instant-read thermometer inserted into the thickest part registers 130° F, 3 to 5 minutes per side for medium-rare. Let rest for 10 minutes before thinly slicing against the grain.
Toss the snap peas, almonds, mint, parsley, lemon juice, ¼ teaspoon each salt and pepper, and the remaining 3 tablespoons of oil in a bowl. Spoon over the steak and potatoes.
The "salsa" was tasty. I'd make this again, but would probably roast the potatoes in the oven. Grilling them is essentially just steaming them which I found a bit boring.
