After about 15-20 minutes of simmering, or whenever the potatoes are fork-tender, it's time to add the cashew cream and blend a portion of the soup. This step is important to achieve that thick and creamy chowder consistency.You can use a high-speed blender or an immersion blender for this step. A high-speed blender will give you a bit of a smoother and more velvety texture, so that is my personal preference, but the immersion blender is a bit easier. High-speed blender: Ladle about 3 cups of the soup into your blender along with the cashew cream. Make sure you're scooping in a good amount of the potatoes and corn, since blending these is what's going to add a lot of richness and body to the soup.Start blending on the lowest speed. Gradually increase the speed and blend until this mixture is as smooth as possible — this usually takes me at least a few minutes. Pour this mixture back into the pot of soup and stir to combine.Important: Please exercise extreme caution when blending hot liquids! Steam can cause the pressure in the blender to rapidly expand and blow the lid off. If your blender lid has a vent, I recommend leaving that open and then covering with a clean kitchen towel, so pressure can escape as you blend.If you are working with a smaller blender pitcher, you may wish to blend in smaller batches, as you don't want the pitcher full when blending hot liquids. Immersion blender: Add the prepared cashew cream into the soup. Then use your immersion blender to blend the soup partially. As you blend, the soup will become thicker thanks to the potatoes and cashew cream. I like to leave the soup fairly chunky, but feel free to blend to your preferred level of texture.
Bring the soup back up to a gentle simmer over low/medium-low heat. Simmer for another 5 minutes to thicken slightly.
Taste and adjust salt and black pepper to preference. You'll need more or less salt based on the kind of vegetable broth you used. Typically I use regular vegetable broth from a carton, and I add about 1 teaspoon fine sea salt. If using a chicken-style veggie bouillon, you'll generally need to add less.
To brighten everything up a bit and balance out the sweetness of the corn, stir in fresh lemon juice just before serving. Serve soup topped with fresh sliced chives or scallions. Tofu or tempeh bacon crumbles are a great addition too.