How to Make It
Toast pumpkin seeds in a dry skillet over medium, stirring constantly, until they begin to puff and turn golden, 4 to 5 minutes. Immediately remove from heat, and transfer to a plate. Cool completely, about 30 minutes.
Return skillet to heat over medium-high. Add scallions, chiles, and garlic, and cook, turning occasionally, until charred on all sides, 4 to 5 minutes. Remove from skillet, and cool completely, about 20 minutes.
Coarsely chop scallions. Remove and discard stems from chiles; remove and discard seeds and veins, if desired. Peel garlic, and discard skin. Place pumpkin seeds, scallions, chiles, garlic, Mexican crema, and 1/4 cup water in a blender. Process until smooth, about 20 seconds. Add cilantro, epazote, salt, and pepper. Process until smooth and crema is the consistency of hummus, about 15 seconds.