Drain (reserve the liquid) and rinse the beans and pulse 5 to 8 times in a food processor until they’re mostly creamy. There should be a few pieces of the beans.
In a large skillet, heat the oil on medium-high heat and add the onion. Cook until translucent and soft, approximately 7 minutes. Add the garlic and spinach and cook until the spinach is just wilted. Remove from the heat.
Add the onion and spinach mixture to the food processor along with the remaining ingredients and pulse 5 to 8 times or until the ingredients are completely combined. Remove the blade from the processor and dived the batter by 4 or 6 (depending on how large you want them to be) and form into patties. Refrigerate for an hour to set.
Heat an oiled grill pan or skillet on medium-high heat. When the oil is hot, add the burgers and cover with a lid. Cook for approximately 4 minutes per side, or until they’re nicely browned and have a crisp exterior. Make sure to cover them so they heat all the way through.
Notes
The Nutrition Facts are an estimate only.If you don’t like to cook with oil, you can sauté the onion and garlic in a few tablespoons of water, but don’t skip the oil for cooking the burgers unless you have a really good non-stick pan.We like pretzel buns for this burger, or if you want to go lower calorie, use a large piece of lettuce to wrap it.Store covered in the refrigerator for up to 4 days. Freeze in a freezer safe container for up to 2 months. Thaw in the refrigerator.