Cut the collard greens away from the stems. Stack several leaves at a time, roll up snugly from the narrow end closest to you, then cut them into thin strips. Chop the strips in a few places to shorten them. Give them a good rinse in a colander.

Heat the oil in a large skillet. Add the onion and sauté over medium heat until translucent. Add the garlic and continue to sauté until the onion is golden.

Add the collards and just enough water to keep the bottom of the skillet moist. Turn the heat up to medium-high and cook, stirring frequently, for 3 to 4 minutes, or until bright green and tender-crisp.

Add the tomatoes, black-eyed peas, and vinegar or lemon juice. Continue to cook until the mixture comes to a gentle simmer, about 3 minutes.

Season with smoked paprika, salt, and pepper, then serve at once on its own in shallow bowls or over hot cooked grain.