Preheat your oven to 400°F (200°C). Lightly grease a large baking sheet with olive oil.

Trim the stems off 1 lb of Brussels sprouts, leaving a bit of the stem to keep each sprout together. Slice each Brussels sprout in half lengthwise through the stem. Arrange the sprouts in a pile on the baking sheet.

In a small bowl, whisk together 3 tablespoons of olive oil and 2 tablespoons of balsamic vinegar. Pour the mixture over the Brussels sprouts, then use your hands to massage it in, ensuring all sprouts are coated. Spread the sprouts into a single layer on the baking sheet, and sprinkle with salt and pepper to taste.

Roast the Brussels sprouts in the preheated oven for 20 minutes. Remove the baking sheet, turn the sprouts over, and roast for an additional 20 minutes or until the Brussels sprouts are fork-tender and crispy on the edges.

Transfer the roasted Brussels sprouts to a large mixing bowl. Drizzle with the remaining 1 tablespoon of balsamic vinegar and toss to coat evenly. Add 1/4 cup dried cranberries and 1/4 cup crumbled feta to the bowl, tossing gently to combine. Taste and adjust seasoning as needed, adding more salt and pepper if desired.