I had never had tri-tip roast from Costco. I came across a recipe that sounded easy so I picked a package up. OMG (just one of the positive reactions it got) it was delicious. Rubbed with salt, pepper and garlic powder, then seared on the grill and finished in the oven at 425°. Done to perfection. Tender and delicious. Medium rare in the center and a little more done on the ends. Would be perfect for a group that likes different levels of doneness. However, I think I'll go for rare next time. And, of course, because it was from Costco, there is another waiting in the freezer. Served it with mashed potatoes and 5 minute gravy (with pan drippings added for extra flavor).