Sauté onions just until translucent (not browned) for sweet, mild flavor., Use low-sodium broth and rinse canned beans to control salt levels., Allow soup to cool before blending and blend in batches with the blender lid slightly open to vent steam., An immersion blender allows blending directly in the pot with less cleanup; blend carefully to avoid hot splashes., If soup is too thick, thin with warm broth or water., Reheat gently on stovetop over medium heat to preserve color and flavor., Store leftovers in the fridge up to 5 days or freeze up to 3 months., Frozen asparagus can be used; add directly and simmer until fork-tender., Add lemon juice or zest and fresh herbs like dill or basil for extra flavor., Swap cannellini beans partially or fully with cooked potato or cauliflower to vary creaminess., Add frozen peas or baby spinach during simmering for added sweetness and nutrients., Top with toasted seeds, crispy chickpeas, croutons, and a drizzle of coconut milk for texture and presentation.