Add ingredients to the jug of your high-powered blender in the order that they are listed in the recipe.
Blend on low initially, slowly moving up to high. Use your blender's tamper to press the ingredients down into the blades. Blend until smooth, but do not allow to melt. Once mixture forms 4 peaks up the side of the jug, it is ready. See picture for example.
Serve immediately or transfer to a bowl and freeze for 30 minutes to firm up slightly. Stir, then serve.
Notes
Making the recipe vegan - I would have liked to make this recipe vegan (without eggs) but it just wasn't coming together. I tried multiple versions with chia seed and many other ingredients, but the egg white protein powder was what made the soft serve soft and fluffy. Without it, the recipe is just mashed peas with cacao powder. Egg White Protein Powder - if you do not have this ingredient, and you're comfortable with it, you could add 2-4 tablespoons of pure egg white. That is about 1 egg white from 1 egg. Coconut sugar - feel free to use any type of sweetener here. If you use a liquid sweetener, you'll likely have to reduce the amount of water from the recipe. Water - you could use dairy-free/non-dairy milk here, too. Almond milk would be nice. Organic Peas - I tried this recipe with organic and conventional peas. What a difference! I highly recommend purchasing ORGANIC for this recipe.
Recipe by Healthful Pursuit at https://www.healthfulpursuit.com/2014/04/brownie-batter-soft-serve-banana-free/