In a large skillet, heat olive oil over medium-high heat. Once the oil is hot, add diced onion and cook until they begin to soften, approximately 3 minutes.
Add turkey and cook until browned, approximately 4-5 minutes.
Remove from heat and add to the bowl of a slow cooker.
Add the remaining ingredients for the chili to the slow cooker. Stir to combine.
Cook on high for 4 hours. Note: you can also make this is in the Instant Pot. Simply add all ingredients to the Instant Pot insert and set to Manual pressure for 25 minutes. Let release naturally.
Serve immediately with listed toppings.