This won't be able to compare with the list that Seth once sent me, but this is a good start. 

https://pairingplates.com/what-to-serve-with-dahl/ 

Cucumber Raita

Cucumber raita, a revitalizing and cooling yogurt-based side dish, serves as an excellent counterpart to the spicy and robust flavors of dahl. Cucumber benefits include hydration and digestive aid, making it a healthy option.

Raita variations can include mint, cumin, or even grated carrots for added texture and flavor. This versatile accompaniment enhances your meal, providing an invigorating contrast to the dahl's warmth.

 

Roasted Cauliflower 

Roasted cauliflower, with its caramelized edges and tender interior, serves as an excellent side dish to complement the hearty flavors of dahl. 

The use of spice blends like turmeric, cumin, and coriander enhances the natural sweetness of the cauliflower, creating a delightful texture contrast. This combination not only adds depth to your meal but also provides a visually appealing and nutritious addition. 

 

Spinach Saag 

Spinach saag, a traditional Indian dish made from pureed spinach and spices, offers a nutrient-rich and flavorful accompaniment to dahl. Rich in vitamins and minerals, spinach saag boasts significant health benefits. For the best flavor, sauté the spinach with garlic, ginger, and cumin before pureeing. This method guarantees a vibrant, aromatic dish that enhances the overall dining experience.