Preheat the oven to 400 degrees. Line a rimmed baking sheet with parchment paper or foil for easy cleanup.
In a large bowl, combine eggplant, red bell pepper, onion, garlic, and thyme. Drizzle with olive oil, 1 teaspoon salt and 1/2 teaspoon pepper and toss to combine.
Spread on prepared baking sheet and roast until the vegetables are soft and lightly browned, about 45 minutes, stirring halfway through roasting time. Cool 5 minutes.
Transfer to a food processor and add tomato paste. Pulse until blended, 3 or 4 times. Transfer to a bowl and stir in lemon juice, red wine vinegar, sugar, and red pepper flakes. Season to taste with salt and pepper. Serve warm or at room temperature.
Eggplant: Look for an eggplant with firm skin and feels hefty for its size. Heavy eggplants tend to be fresher and more hydrated than their lighter, similarly-sized peers. Avoid eggplant with any soft spots, discoloration, or wrinkling.
Tomato paste: Since you'll only need 1 tablespoon for this Roasted Eggplant Dip, try to find the tomato paste in a tube rather than a can to extend its life. Cento, Amore, and Tuscanini all offer tubes of tomato paste that tend to be widely available across America and online.
Crushed red pepper flakes: Not a fan of heat? Simply omit the pepper flakes. Prefer it fiery? Add extra!
Yield: This recipe makes six snack-sized servings of Roasted Eggplant Dip; each slightly more than 1/3 cup.
Storage: Store leftovers covered in the refrigerator for up to 4 days.