Add the green cabbage, red cabbage, carrot, and green onion (if using) to a large mixing bowl. Toss gently to combine, keeping the vegetables loose rather than compacted—this helps maintain their crisp texture.

In a small bowl or jar, whisk together the lemon juice, olive oil, honey, salt, and pepper until well combined. The dressing should taste bright and balanced, with enough acidity to cut through richer foods.

Pour the dressing over the cabbage mixture. Using tongs or clean hands, toss gently but thoroughly until everything is evenly coated. Avoid over-mixing, which can bruise the cabbage and draw out excess moisture.

Let the coleslaw sit for about 10 minutes before serving. This short rest allows the lemon dressing to soften the cabbage slightly while keeping it crisp.