To prepare the soup, we'll begin by boiling 1.2 liters (5 cups) of water.
While waiting for the water to boil, we'll wash and chop the vegetables. First, we'll sauté the onion in hot oil until it turns brown around the edges.
Then, we'll add the chopped asparagus and a pinch of salt, and sauté everything for around 5 minutes over medium-high heat.
Step 2: Add spinach and water
Next, we'll add the spinach and pour in hot water. We won't completely submerge the spinach, as it will soften and lose volume during cooking. We'll just stir it around a bit to cook it evenly. It's important not to add too much water, as we don't want a watery soup.
Step 3: Add heavy cream and blend
After cooking everything together for 15 minutes with a pinch of pepper and 1 teaspoon of salt, we'll turn off the heat and add heavy cream.
We'll then use a blender (such as a stand blender, food processor, or immersion blender) to blend the soup until it's creamy and smooth.
Notes
To store this soup, let it cool to room temperature, place it in an airtight container, and refrigerate for up to 3-4 days.