Vegan brown lentil soup

Ingredients:
1 cup dried brown lentils
1 tablespoon olive oil
1 onion, diced
2 cloves garlic, minced
2 medium carrots, diced
2 celery stalks, diced
1 teaspoon ground cumin
1 teaspoon smoked paprika
1 teaspoon dried thyme
1 bay leaf
4 cups vegetable broth
Salt and pepper to taste
Fresh parsley, chopped (optional)