Saute onion in oil for 3-4 minutes until soft. Add garlic and saute for 30 seconds more, until fragrant.
Add sweet potato, broth, thyme, salt, garlic salt and pepper, then bring to a boil and cook for 10-12 minutes, or until sweet potatoes are fork-tender.
Add in the chicken, paprika, and corn.
Whisk together the milk and flour, then pour into the chowder slowly, stirring as you pour. Bring the chowder back to a boil, then thicken for 6-8 minutes. Adjust salt and pepper to taste.