Mix the oil with the garlic and ginger and distribute around the tenderloin. Let marinade overnight covered.
On the next day remove the garlic and ginger and season with salt and pepper.
Heat a bit of vegetable oil in a pan on high heat. Seal the tenderloin on all sides until really golden. You'll see smoke coming out and that's normal because of the sugar caramelizing.
Take to a preheated oven at 180C for 15-20min or until the temperature at the center reaches 63C. We don't want to overcook it or it will dry out.
Take off the oven and let it rest covered in tin foil for 10min so the juices don't come rushing out when we slice it.
Put everything in a pot and let it boil until it thickens. Remove the garlic.
Whisk together the dressing ingredients and marinade the cucumbers and radishes in the dressing separately for about 10min.
Garnish with black sesame seeds.