Bring a large pot of water to a boil. Add the kale and cook until just tender, 1 to 2 minutes. (This can also be done in the microwave. Add the kale to a large microwaveable bowl, cover with warm water and microwave on high for 2 to 3 minutes.) Drain and squeeze out any excess water. Set aside.
Add the oil and onions to a large skillet and cook over medium heat, stirring, until the onions are translucent, 2 to 3 minutes. Add the kale, cream, bean puree, cream cheese, Parmesan and red pepper flakes and stir. Cook until the cheese is melty, 1 to 2 minutes. Taste and adjust seasonings with salt and pepper. Pour into a small casserole dish, top with the nuts and bake until bubbling and gooey, 15 to 20 minutes. Serve with sliced baguette or tortilla chips.
White Bean Puree:
Add the white beans to a food processor. Pulse 3 to 4 times to break up the beans. With the machine running on low speed, stream in 1 tablespoon of the oil. If the puree looks dry, stream in 1 more tablespoon.