Place a medium (to large) saucepan over medium-high heat, then add olive oil.
Once it's ready, saute the garlic and onion until they soften.
Add the Spanish paprika and bouillon cubes, and cook for 2 minutes. Try to mix continuously to avoid burning, and lower the heat if you think it's necessary.
Add the carrots and the bits of Jamón Serrano; then mix.
Pour 3.5 cups of water, then add the bay leaf, crushed tomatoes, sherry, and rinsed lentils.
Mix, cover with a lid, and bring to a boil.
Lower the heat and simmer for at least 30 minutes, or until the lentils or vegetables are cooked.
Add the vinegar and salt, then stir.
Taste and adjust the seasoning as desired, then remove the saucepan from the heat.
Transfer your Spanish lentil soup into bowls --- serve and enjoy!