Lay the strips of bacon flat on a rimmed baking sheet and place in the oven, about 15 minutes. Set aside to cool slightly.
While the bacon is in the oven, trim the brown ends from the Brussels sprouts and cut each in half. Reserve the dark green leaves and discard any brown or yellow leaves. Transfer to a large bowl and toss with 1 teaspoon kosher salt, garlic, and vegetable oil.
Remove the bacon from the baking sheet and place on a paper towel lined plate. Pour about 2 tablespoons of the rendered bacon fat over the Brussels sprouts and toss to coat. Transfer to the warm sheet pan, spreading the Brussels sprouts in a single layer, and season with additional Kosher salt.
Return the baking sheet to the oven and roast until the Brussels sprouts are well browned and tender, 15 to 20 minutes. Remove the baking sheet from the oven and stir with a spatula halfway through the cooking.
While the Brussels sprouts are in the oven, combine the raisins and vinegar in a small saucepan and bring to a boil. When the pot reaches a boil, remove from the heat and set aside to cool.
To serve, drain any vinegar that may remain from the raisins and roughly chop the bacon. Transfer the roasted Brussels sprouts to a serving bowl, add the bacon and drained raisins and gently toss to combine. Sprinkle Parmesan cheese over the top and serve.