Combine all the spices for the spice rub in a small bowl and stir to combine.
Prepare a grill to medium high heat and brush with olive oil. Brush the corn with the oil. Grill the corn and poblano pepper, turning occasionally, until charred, about 8–10 minutes and remove from the grill and let cool. Strip the kernels from cobs and place in a medium bowl. Peel the charred skin on the poblano and discard. Chop the flesh of the pepper into a small dice and add to the bowl with corn kernels. Discard seeds from the poblano
Add onion, jalapeño, tomatoes, cilantro, and lime juice to corn and toss to combine; season with salt and pepper. Set salsa aside.
Meanwhile, drizzle the steak with 1 tablespoon of oil and sprinkle the steak with all of dry rub. Grill the steak, until you have grill marks on both sides. (4 minutes per side for medium-rare, 5 minutes per side for medium.)
Transfer to a cutting board and let rest 10 minutes.
After 10 minutes, slice against the grain and top with the salsa.