Preheat your grill to medium-high heat and preheat your oven to 400°F.
Prick the eggplant several times with a fork and roast it whole on a baking sheet for 35 minutes until the skin is charred and the flesh is very soft.
Once the eggplant is cool enough to handle, scoop out the soft flesh into a bowl and discard the skin.
Mash the eggplant flesh with tahini, lemon juice, minced garlic, ground cumin, and a pinch of the sea salt until it reaches a smoky and creamy consistency.
Rub the sirloin steak with olive oil and season both sides evenly with the remaining sea salt and black pepper.
Grill the steak for approximately 4 to 5 minutes per side for a medium-rare finish, then transfer to a board to rest for 5 minutes.
While the steak rests, toss the diced cucumber and tomato with the chopped fresh parsley in a small bowl.
Spread the baba ghanoush onto a plate, slice the steak against the grain, and arrange the beef over the eggplant dip, finishing with the fresh salad on top.