In a large pot, heat olive oil over medium heat. Add chopped onion, garlic, carrots, and celery. Saut? until the vegetables are softened, about 5-7 minutes.

Add the rinsed split peas, vegetable broth, thyme, bay leaf, salt, and pepper. Bring to a boil.

Reduce heat to low, cover, and simmer for about 60 minutes, or until the peas are tender.

Remove the bay leaf. For a creamier texture, blend a portion of the soup using an immersion blender or transfer to a countertop blender.

Serve hot, garnished with additional black pepper or fresh herbs if desired.