Preheat your grill to medium-high heat, aiming for a temperature around 400°F.
In a small bowl, whisk together the smoked paprika, ground cumin, garlic powder, onion powder, chipotle powder, sea salt, and black pepper to create the rub.
Slice the sweet potato into 1/2-inch thick rounds and trim the tough woody ends off the broccolini.
Pat the sirloin tip steak dry with paper towels, then coat with 0.5 tablespoon of olive oil and apply the smoky rub generously to all sides.
Toss the sweet potato rounds and broccolini in a bowl with the remaining 1 tablespoon of olive oil and a small pinch of extra salt.
Place the sweet potato rounds on the grill first, as they take the longest; cook for 4-5 minutes per side until tender and marked with grill lines.
Add the seasoned steak to the grill and cook for approximately 5-6 minutes per side for a perfect medium-rare finish.
During the final 4 minutes of the steak's cooking time, place the broccolini on the grill, turning occasionally until the florets are slightly charred and the stalks are crisp-tender.
Remove the steak from the heat and let it rest on a cutting board for at least 5-10 minutes to allow the juices to redistribute.
Slice the steak thinly against the grain and serve immediately alongside the grilled sweet potatoes and charred broccolini.