Add enough water to cover everything by 1 inch. Bring the water to a rolling boil over medium-high heat, then reduce to low and let simmer until the lentils are tender but not mushy, about 30 minutes. Drain the lentils, discard the cinnamon and garlic, then transfer the lentils to a large bowl.
Roast the squash until completely tender, slightly caramelized and golden brown, about 40 minutes. Remove from the oven, and let cool for 10 minutes. Once cool, add to the lentils.
While the squash cooks, prepare the dressing: In a mason jar, add the olive oil, pomegranate molasses, honey, cumin, cayenne and black pepper. Put on the lid and shake vigorously. Taste and season to taste with salt.
Sprinkle the feta, scallions and pumpkin seeds over the lentils and squash. Pour 2 to 3 tablespoons of the dressing over the lentils and squash. Serve warm or at room temperature, with the remaining dressing on the side.