Make your pesto by combining basil, kale, olive oil, cashews, and a pinch of salt in the food processor.
Heat a drizzle of olive oil in a pan over medium heat.
Add your peas and sauté them for 3-5 minutes, then remove them from the heat.
Decrease the heat to low, and add the butter. Once the butter has melted, add the flour and mix for 1 minute until everything is well combined.
Add ½ c of the milk until the consistency thickens significantly and the roux easily separates.
Increase the heat to medium low, add the next ½ c of milk, then stir until the roux thickens again, about 10 minutes. It should be thick enough that you can draw a line between the roux with a spatula or spoon.
Add about ¼ c of the pesto or more based on your preference. Stir to combine completely.
Add a pinch of salt to taste and lemon juice, and stir to combine. Then, add the butter beans after draining and rinsing them.
Turn off the heat, then add lemon zest on top, and dill.
