Heat olive oil in a medium pot over medium-low. Add onion, jalapeño, garlic, salt, and pepper and sauté until softened - about 5 minutes. Stir in corn kernels and cook an additional 5 minutes - until corn is heated through. Transfer to a blender and blend while slowly pouring in chicken broth. Return to pot and cook until heated through - about 10 minutes over medium heat. Serve immediately topped with avocado salsa.