Add the rinsed split peas, diced onion, carrots, celery, potato, and minced garlic to a large pot.
Pour in the vegetable broth and add the bay leaf and dried thyme.
Bring the mixture to a boil over medium-high heat, then reduce to a simmer.
Cover the pot and cook for 45 to 50 minutes, stirring occasionally, until the split peas are soft and the vegetables are tender.
Remove the bay leaf. Use a potato masher or immersion blender to partially blend the soup for a thicker texture if desired.
Season with salt and black pepper to taste before serving.