Prepare a simple ice bath by adding ice cubes in a large, wide bowl about half-way up. Add cold water about half-way up. Set aside.

Heat a medium-large pot filled half-way with water over high heat. Once water is boiling rapidly, carefully add green beans. Cook for 2 to 3 minutes. Immediately empty beans into a large colander, letting hot water drain into sink. Then place colander of  hot beans directly into the ice bath. This will stop the beans from cooking further. If you like your green beans on the crisper/raw side, skip the blanching process altogether or blanch for less time.

While beans are chilling, prepare the teriyaki-ginger sauce. Add soy sauce, mirin, sesame oil, brown sugar, honey, ginger, and garlic to a small saucepan over medium heat. Bring to a boil, and then stir constantly for one minute. Reduce heat just a bit. In a very small bowl or cup, whisk together cornstarch and water. Whisk cornstarch slurry into teriyaki-ginger sauce until incorporated. Let cook for about 5 minutes, until sauce has thickened a bit. Remove from heat.

Drain green beans thoroughly from ice bath. Place a large cast iron skillet (mine is 12" wide) over medium-high heat and allow to heat thoroughly, until skillet is very hot. Once hot, add the Land O Lakes® Butter with Olive Oil & Sea Salt and then quickly add the green beans and toss a few times to coat evenly. Turn the heat up just a bit, then let the beans sit on the hot skillet to char and blister. This process is quite noisy, as the beans crackle and pop in the hot skillet. After a minute or two, peek at a green bean that is in direct contact with the bottom of the skillet. If it is blistered, then give all the beans a toss, letting other beans get some blistering time on the hot skillet.

Repeat this process once more, until you have a good amount of blistering. Then drizzle 1/3 cup of the prepared teriyaki-ginger sauce over the charred beans (store remaining sauce in refrigerator for another use - it's great over any fresh vegetables). Very quickly, toss the beans a couple times to coat, and then immediately remove beans from the skillet to a serving platter. You will need to work quickly. If left even just a little too long in the skillet, the sugars in the teriyaki-ginger sauce will burn with the high heat.

Sprinkle beans with some flaky sea salt, freshly ground black pepper, and toasted sesame seeds. If desired, also sprinkle with red pepper flakes. Serve immediately.