Onions clean. Take a toothpick (or broken in half wooden skewers). For bulbs of average size, we need 5 toothpicks. Stick one toothpick in the center of the bulb. 2 toothpicks need to place the left and right of center about the same distance from each other. Stick the toothpick deep enough. For clarity, enhance photos.

Cut the onion into rings between the toothpicks stuck. Turns out the "bow stick".

Mix vegetable and melted butter, black pepper.

Mix soy sauce, honey and mustard, mix well.

Lubricate the onions on both sides with oil mixture and put on preheated grill (medium-high fire). I used the convection oven 220 degrees. Cook for 10 minutes, not forgetting occasionally turn and brush with oil mixture.

Grease onion soy-mustard mixture, cook 2 minutes. Then bow flip and brush the other side. Leave on the heat for another 1 minute.