Combine the olive oil, seasoned vinegar, red wine vinegar, sugar, garlic, sea salt, and freshly cracked pepper to taste. Whisk until evenly combined. Let the vinaigrette sit for 20-30 minutes to allow flavors to mingle.
Place the broccoli florets in a steamer tray placed in a large saucepan of boiling water.
Once the water is boiling, place a lid on the saucepan and steam for 3-4 minutes or until broccoli is fork-tender.
Remove from the pot of water and steamer immediately.
Pour the broccoli into a serving bowl, then drizzle it with the vinaigrette and season with sea salt and freshly cracked pepper, to taste. Toss to coat the broccoli evenly.