Preheat oven to 350°F. Line a standard 12-cup muffin tin with paper baking cups.
Whisk together the flour, baking powder, baking soda, guar gum and salt in a large bowl. Make a well in the middle.
Add the grapeseed oil, coconut nectar and stevia and stir to combine. Add the grape jelly, sunflower seed butter and rice milk and stir until the liquid is absorbed.
Spoon the batter into the prepared muffin tin, dividing it evenly. Each cup should be about three-quarters full.
Bake the muffins for 15 to 17 minutes, or until they are a light golden brown and bounce back slightly to the touch. Rotate the muffin tin from front to back halfway through baking.
Transfer the muffin tin from the oven to a wire rack and let sit for 10 minutes before removing the muffins to cool completely.
Keep in an airtight container for up to 3 days, or wrap and freeze for up to 3 months.