Preheat your oven to 400°F and line a large baking sheet with parchment paper for easy cleanup.
Trim the woody ends off the asparagus and peel the carrots, slicing them into thin sticks of similar size.
Toss the asparagus and carrots on the baking sheet with half of the olive oil and a pinch of the salt and pepper.
Roast the vegetables for 15 to 18 minutes until they are tender and slightly charred at the edges.
While vegetables roast, finely dice the pineapple and mince the garlic clove.
In a small bowl, combine the diced pineapple, minced garlic, and red pepper flakes to create the spicy glaze.
Season the sirloin steak on both sides with the remaining sea salt and black pepper.
Heat a cast-iron skillet over medium-high heat with the remaining olive oil and sear the steak for 3 to 4 minutes per side.
Add the pineapple mixture to the pan during the last minute of cooking to warm it through and lightly caramelize the fruit.
Toast the sourdough bread until golden, then let the steak rest for 5 minutes before slicing and serving with the roasted vegetables.