Hi DeePee,
Lentils, especially the small orange ones, are inconspicuous enough to be "hidden" in many dishes - soups, stews, pasta, and even salads. If you cook orange lentils long enough, they soften into a thick broth.
Lentils are a popular ingredient in several regions - in Spain, Portugal, Italy, Greece, the Middle East, North Africa, and India.
In Northern Spain, lentil and potato soup is a popular home-cooked dish. I ate it when I visited Spain on business.
In Portugal, "caldo verde" - a potato and kale soup that sometimes includes lentils - is also a popular home-style dish. My dad is part Portuguese, and he has always liked lentil soup.
In Italy, lentil, pasta, and vegetable soups are popular. My mom's father was Italian, and he always liked some beans or lentils at dinner.
In the Middle East, pureed lentil soup is popular.
In India, lentils are a daily staple food, made into soups, stews, and as an ingredient in some breads.
On YouTube, there is a super-cute Italian grandma with her own cooking show. She's very popular!
In this video, she makes lentil soup (though it has more ingredients than my lazy self prefers to use):
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