Heat 1 tablespoon of the oil in a small saucepan. Add the diced shallot and sweat for 1-2 minutes until softened. Add the spices and cook for another minute.
Pour the entire can of cannellini beans into the saucepan (don't drain!) and bring to a simmer. Gently mash the beans with a potato masher or the back of a wooden spoon until they're mostly broken down. Simmer over a medium heat for 5-10 minutes until thickened. Season with salt and pepper to taste - bear in mind that beans can take quite a lot of salt so you might need more than you think.
Snap the woody ends off the asparagus and cut into short lengths - about 1cm. Leave the tips intact. Heat the remaining oil in a frying pan over medium-high heat and add the asparagus and frozen peas. Saute for 5-10 minutes until golden and the asparagus is tender. Season to taste with salt and pepper.
I like to warm my tortillas in a dry frying pan so that they get a bit browned and charred but you can warm them in the oven if you prefer. Serve the warmed tacos with some refried beans, asparagus and peas and lots of toppings!