Into a medium-size saucepan over medium-high heat, add vegan butter. When the butter is melted, add red onion. Saute 1-2 minutes, until tender.
Add chopped broccoli, quinoa, chicken-style broth, sea salt, and ground black pepper. Reduce heat to low.
Cover and simmer 15 minutes, or until liquid is absorbed.
Stir in vegan Cheddar cheese, replace the lid, and set aside and allow the cheese to melt.
Adjust seasoning to taste and serve hot.