Sprinkle garlic with salt and mince to combine, then mash to a paste with flat side of chef's knife. In a small bowl, mix paste with paprika, pepper, and 2 tbsp. oil. Spread paste all over tri-tips. Wrap meat in plastic wrap and chill at least 24 hours and up to 2 days.
Preheat oven to 350°. Scrape excess marinade from meat. Heat remaining 1 tbsp. oil in a large, ovenproof frying pan over medium-high heat. Brown tri-tips on one side only, 3 to 4 minutes. Turn meat over in pan; then set in oven and roast until internal temperature reaches 125° for medium-rare, about 20 minutes. Let meat rest, uncovered, on a cutting board 15 minutes.
Meanwhile, make salsa: Put all salsa ingredients in a food processor and pulse several times to combine into a rough sauce.
Slice each tri-tip thinly across the grain, rotating the meat to keep knife perpendicular to the grain (it changes direction on tri-tip). Serve with salsa.
This marinade is easy, simple and amazing! We didn't have time to cook it after 24 hours so we lett it set for another day, and this is the best tri tip I have ever made. This will be our new recipe for when we have company over.
I've made this three times, and every time had only a couple hours to let it marinate wrapped in Saran Wrap in the fridge, rather than the 24 hrs in the recipe ("at least 24hrs"). Each time got raves, and each time I vow to be sure I get it in the marinade a day ahead, cos if it's this good while disobeying the directions, how great would it be if I was in full compliance??! Then I forget and have to rush it. :-/.
As a person who avoids spicy food, I have no idea WHAT compelled me to add a bit of chile powder, but add it I did, and liked it a lot. Only about 1/2 to 1 teaspoon, for one tri tip (this recipe is for two tri tips total about 5 lb). It just gave it a bit of spark I'm not used to when cooking my tri tip my usual way.
Try this recipe! Also I actually started it on the stove top, in my big black skillet, and finished it in the Weber IN THE SKILLET! It was great.