Cut jalapeño into 1/4-inch slices. If you want your sandwich less spicy, use a paring knife to remove the seeds and veins.
Adjust cooking rack to the top placement and select the BROIL setting. Place jalapeño slices on a baking sheet, and broil until they have softened and are just starting to brown, about 2 to 4 minutes. Remove pan and set aside.
Make the Sandwich:
Adjust the cooking rack to the bottom position. Place an empty sheet pan inside of the toaster oven, and preheat to 400°F on the BAKE setting.
Spread one side of each slice of bread with mayonnaise. Place the bread mayo-side-down on a cutting board.
In a small bowl, combine the cream cheese, green onion, and garlic powder. Spread each slice of bread with the mixture. Arrange jalapeño slices in an even layer on one slice and distribute the cheese evenly over both pieces of bread.
Carefully remove the pan and add the bread, mayo-side-down, to the pan. Return to the oven and bake until the bread is toasted and the cheese is melted and bubbly, about 6 to 7 minutes.
Drizzle the honey over the jalapeño and sprinkle with corn flakes. Immediately top with the remaining cheesy bread slice and dig in!