Rinse and drain the soaked cashews. Place them, 1/4 cup water, the can of tomatoes, garlic, just 1/4 cup of basil (ignore the quantity below - it's a technical issue I can't fix), salt and pepper to a high-speed blender like a Blendtec.
1 cup (130 grams) raw cashews, 1/4 cup (60 ml) water, 14.5 oz (400 grams) canned tomatoes, 1 1/2 teaspoons garlic, 1/2 cup (12 grams) basil, 3/4 teaspoon salt, 1/4 teaspoon black pepper