Add the chopped onion and minced garlic to the slow cooker along with a tablespoon of olive oil. Set it to low and cook for about 15 minutes, until the onion is translucent and fragrant, filling your kitchen with a sweet aroma.
Pour in the vegetable broth, ensuring it covers the onion and garlic. Turn the slow cooker to high and let everything simmer gently for 30 minutes, allowing the flavors to meld and the broth to develop a savory aroma.
Stir in the fresh spinach in batches, giving each handful a few minutes to wilt and turn a deep, vibrant green. The spinach will soften and release a fresh, earthy aroma as it cooks down.
Use an immersion blender directly in the slow cooker or carefully transfer the hot mixture in batches to a blender. Blend until the soup is silky, smooth, and velvety, with no visible chunks, about 2-3 minutes. Be cautious with hot liquids—blend in small portions if using a traditional blender.
Return the blended soup to the slow cooker (if needed) and stir in the cream or coconut milk. Warm through for another 5 minutes, then squeeze in fresh lemon juice to brighten the flavors. Taste and season with salt and pepper as needed.
Once everything is heated through and seasoned perfectly, turn off the slow cooker and let the soup rest for a few minutes. This helps the flavors meld beautifully and the soup to thicken slightly.
Serve the soup hot, garnished with a drizzle of olive oil or a few fresh spinach leaves for a beautiful presentation. Enjoy the velvety texture and vibrant flavor of this nourishing green goodness.
