Rinse the lentils thoroughly under cold water until the water runs clear, then set aside.
Heat the olive oil in a large heavy-bottomed pot over medium heat until it shimmers and begins to ripple.
Add the diced onion to the pot and cook, stirring often, until translucent and fragrant, about 5 minutes. You should hear a gentle sizzling and see the onions turn clear.
Stir in the grated fresh ginger and cook for about 1 minute until fragrant, releasing a warm, spicy aroma.
Sprinkle in the turmeric powder and stir constantly for 30 seconds to toast the spice, watching for a deepening golden color and fragrant aroma.
Add the chopped carrots to the pot, stirring well, and cook for 3-4 minutes until they start to soften and turn slightly tender, with a hint of sweetness in the air.
Pour in the vegetable broth, bringing the mixture to a gentle simmer. Once bubbling, add the rinsed lentils and a pinch of salt, then reduce the heat to low.
Let the soup simmer uncovered for about 25-30 minutes, stirring occasionally. The lentils should become tender and slightly break down, creating a thick, velvety texture, while the vegetables soften and meld with the spices.
If using greens, stir them in now and cook for an additional 5 minutes until wilted and tender.
Taste the soup and adjust the seasoning with salt and pepper. For added brightness, squeeze in a little lemon juice or vinegar if desired.
Turn off the heat, let the soup rest for a few minutes to allow flavors to meld, then ladle into bowls and serve hot, optionally drizzled with a bit of olive oil or garnished with herbs.