1. Trim the stems from the jalapeños. Slice them down the center from top to bottom and scrape out the seeds with a spoon. Dice the jalapeños and add them to a small saucepan.
2. Add the sugar and water to the saucepan and cook over medium heat, stirring until the sugar has dissolved.
3. Reduce the heat to low and simmer the jalapeños until the liquid has thickened and candied the jalapeños, about 10 minutes. Turn off the heat (the liquid will thicken more as it cools). Let the candied jalapeños cool completely.
4. In a large bowl, stir together the cornmeal, flour, baking powder, salt and cornstarch. Pour in the milk and stir to fully combine.
5. If there is excess liquid in the saucepan containing the jalapeños, drain it. Fold the cooled candied jalapeños and scallions into the batter, making sure they are evenly distributed.
6. In a large skillet, heat one-and-a-half to two inches (3 and 3/4 – 5 centimeters) of oil to 350 degrees Fahrenheit (177 degrees Celsius). There should be tiny bubbles in the oil.
7. Drop large dollops of the batter into the hot oil, being sure not to overcrowd the skillet. Fry the hushpuppies on each side for about two minutes, or until they are golden brown. Place the hushpuppies on a paper towel when they are done, and repeat this process with the remaining batter.
8. Just before serving the hushpuppies, whisk together the butter and agave syrup in a small bowl.
9. Serve the hushpuppies with the sweet butter.