Preheat the oven to 220 degrees C°/425 degrees F°
Soak the cashews in hot water 15-20 min. Drain and rinse.
To a high-speed blender, add the cashews, water, nutritional yeast, salt, red pepper flake, black pepper, and vinegar. Blend on high until creamy and there are no chunks of the cashews left. Taste the sauce, it should taste delicious! Add more vinegar if you want more tang or more salt if you prefer.
Preheat oven to 425F. Heat oil in a large skillet and add the onion and a pinch of salt over medium-high heat, cook for a few minutes until it starts to turn translucent. Lower the heat to medium, add the garlic and cook for another 2 minutes, stirring often.
Add the onion and garlic, spinach, and drained artichokes to the blender. PULSE, (don´t blend!) Until combined and chopped into smallish pieces.
Add the mixture to a square or round baking dish (pie pan size) and bake in the oven for 20 minutes until warmed through and the top starts to brown.
Enjoy with tortilla chips, pita bread, or toasted baguette slices! This Vegan Spinach Artichoke Dip stays good in the fridge for 4-5 days and can be frozen for longer storage. When reheating after being frozen, allow to defrost completely and then either reheat in the oven or in a saucepan if you only have a small amount.