Start by greasing your muffin tin or silicone muffin cups with oil spray.
In a large mixing bowl, whisk together the all-purpose flour, yellow cornmeal, cornstarch, salt, baking powder, and baking soda.
In another bowl, beat the eggs until they’re light and fluffy. Then add the canola oil, honey, brown sugar, buttermilk, and sour cream. Whisk until everything is well combined.
Pour the wet mixture into the bowl with the dry ingredients. Gently fold them together using a spatula until just combined.
Spoon the muffin batter into the prepared muffin cups, filling each about 2/3 full.
Add 1 cup of water to the bottom of your Instant Pot. Place a trivet inside and set the muffin tin on top.
Close the lid, set the steam release valve to sealing, and cook on high pressure for 10 minutes. Let the pressure release naturally for 5 minutes.
Carefully remove the muffin tin from the Instant Pot and let the muffins cool for a few minutes before transferring them to a wire rack.