PREPARE INGREDIENTS: Preheat grill to medium-high heat (400-450 degrees F.) Shuck corn. Remove stems and halve zucchinis lengthwise. Halve or quarter cherry tomatoes, depending on their size. Halve both lemons; juice one of the lemons to get 1/4 cup juice and set the other two lemon halves aside to grill. Rub or brush (with a pastry brush) corn and zucchini with olive oil. Season liberally with salt and pepper (I add about 1 to 1/2 tablespoons oil and about 1/2 teaspoon salt and pepper).
CORN ZUCCHINI SALAD: Prepare the preheated grill by cleaning with a grill brush. Generously oil the grill (I drench a rolled-up paper towel in vegetable oil and, holding it with tongs, rub it over the grill grates). Add corn and zucchini. Cook zucchini about 2-3 minutes, flip and cook another 2-3 minutes or until lightly charred and crisp-tender. Cook the corn, rotating about every 2-3 minutes (a total of 4 rotations) until charred, bright yellow, and crisp-tender about 10-12 minutes total. Grill lemon halves flesh side down for 2-3 minutes or until charred. Transfer vegetables to a cutting board to cool slightly. Slice corn off the cob and add to a large bowl. Cut zucchini into thin half moons and add to the bowl with the corn. Add in the cherry tomatoes, Parmesan cheese (to taste), and fresh basil (rip or cut into ribbons). Add in the juice from one half of the grilled lemon (about 2 tablespoons) and some additional olive oil (about 1 to 2 tablespoons). Toss and taste, adjust seasonings by adding any additional salt, pepper, or oil.
COOK STEAKS: While vegetables and lemon are grilling, pat steaks dry with paper towel and rub with olive oil (about 1/2 tablespoon per steak). Season both sides generously (or to taste) with salt and pepper (I add about 1/2 teaspoon fine sea salt per steak). Add steaks to the fully heated grill and cook until charred and medium rare (or to temperature preference, medium rare highly recommend) about 4-5 minutes per side. (For 1-pound steaks, medium rare generally takes 4 minutes per side); use a food thermometer for precision (see temperatures in post). Transfer steaks to a plate to rest for about 5-10 minutes, tented with foil. Transfer to a cutting board and cut across the grain as thinly as possible (this makes sure the meat is tender!)
SAUCE: While steaks grill, finely mince garlic and coarsely chop the sundried tomatoes. Add garlic and tomatoes to a small blender or food processor. Add in the 1/4 cup lemon juice and salt and pepper (I add about 1/2 teaspoon salt and 1/4 teaspoon pepper) and pulse until ingredients are chopped. Slowly drizzle in the oil (I use all the oil from the sundried tomatoes container and fill up the rest of the 1/2 cup with regular oil) and pulse until emulsified and a chunky sauce has formed. Taste and adjust seasoning.
ASSEMBLE: Add thinly sliced steak to plates (1/2 steak per plate). Divide the corn-and-zucchini salad among the plates. Spoon the sauce evenly on the steaks. Garnish the dish with additional Parmesan. Cut the remaining half of the grilled lemon into wedges and add one wedge to each plate. Squeeze lemon over before enjoying!