Caramelize the onions: 
Heat the olive oil in a large heavy pot or Dutch oven. Cook the onions over medium heat for 10–15 minutes until deeply golden and caramelized.

Build the cholent: 
Add the barley, beans, potatoes, yams, and Holy Plantz tempeh to the pot.
Sprinkle over the paprika, garlic powder, onion powder, salt, and black pepper. Add the soy sauce and silan, then mix everything together.

Add the water:
Pour in enough boiling water to generously cover everything. The cholent should look fairly liquid before the overnight cook, as the barley will absorb a lot of moisture.

Slow cook overnight:
Bring to a gentle simmer, cover tightly, and cook:
In the oven at 100-110°C overnight for 10-12 hours - or in a slow cooker on low for 12–14 hours. Check once or twice during cooking and add extra water if needed.

Serve:
By morning, the beans should be soft, the barley creamy, the potatoes buttery, and the tempeh packed with deep savory flavor. Serve hot with tahini, pickles, zhug, or fresh challah.