Step 1

Preheat the oven to 400° F and line a rimmed baking sheet with parchment paper. Put the sweet potatoes on the lined baking sheet and prick each several times with a fork. Bake for 45 to 60 minutes, until fork-tender.

Step 2

Meanwhile, cook the lentils according to their package instructions. Drain well.

Step 3

Heat the oil in a large skillet over medium heat. Add the cumin seeds and cook, stirring constantly, for 1 to 2 minutes, until the seeds start to pop. Add the onion and cook, stirring occasionally, for 5 to 7 minutes, until tender and translucent. Add the garlic and tomatoes and cook, stirring frequently, for 1 to 2 minutes, until the garlic is fragrant.

Step 4

Decrease the heat to low and stir in the lentils, ginger, cinnamon, paprika, harissa, and salt, then stir in the spinach. Cook, stirring frequently, until the spinach has wilted, adding water by the 1⁄4 cup if needed to prevent sticking. Stir in the pomegranate molasses. Taste and adjust seasonings if desired.

Step 5

Cut each sweet potato in half and use a fork to coarsely mash the flesh, still in the skin. Place two halves on each serving plate and top them with a generous scoop of the lentils. Serve right away, with a drizzle of the tahini dressing and the optional fresh herbs.

Step 6

Combine all the ingredients, plus 1/4 cup warm water, in a small bowl or measuring cup and whisk until evenly blended. If the dressing is thicker than you’d like, whisk in water by the tablespoonful to achieve the desired consistency. (Stored in an airtight container in the refrigerator, the dressing will keep for 1 week.)