Grilled Oysters Mayo Gratin

This recipe is a recreation of one of my favorite dishes at one of my favorite restaurants - Hotaru. Hotaru calls it "grilled oysters mayo cheese gratin" - roughly. Their dish is shown in the picture below.

It's oyster season in Japan. They are being widely sold in stores and restaurants are now featuring them. The Oyster House restaurant has even opened up again for its second year near Verny Park.

Hotaru Grilled Oysters Mayo Gratin

Served with some toast - simply spoon the oyster and some of that savory juice onto the toast and eat - it's very good.

While the exact ingredients of the restaurant version are not known, we can come close and add some creativity of our own. A search in Japanese on the Japanese recipe website Cookpad.com or Google is always a good place to start. I took the first part of the entry for this dish on the menu (which looks like this - 牡蠣のマヨネーズ焼き)  and did a search. Cookpad will be one of the Google results and then just use your page translator. Cookpad will have many recipes from which to choose. Cookpad also has an English language site that you can view Japanese recipes on as well, although nowhere near the amount posted on their Japanese site.

Many of the recipes I came across used white wine, but I didn't have any. So - in line with the Japan theme of recipes here - I went with sake, or "nihonshu" instead.

Some of the ingredients

The ingredients:
- oysters (about 20)
- bag of small "bread toasts"
- 4 tbsp bread crumbs or panko 
- 4 tbsp Parmesan cheese
- 3 cloves garlic, minced
- 2 tablespoons mayonnaise
- 200 ml water
- 200 ml sake (or white wine)
- salt, pepper
- chopped parsley
- butter

Oysters in the package

The top pack (from Miyagi) were noticeably larger and supposedly have better taste. The oysters in the bottom package were from the Hiroshima area. A nice article about farming them in Hiroshima is here. "Oyster" in Japanese is kaki (pronounced ka-key). Both packages say raw kaki - 生かき.

 First some prep work.

Preheat oven to 400F. 

 Combine the bread crumbs and Parmesan. Fresh grated Parmesan would be better of course. Although I didn't try it, I bet some Gruyere cheese would be good too.

 Mince the garlic and combine with the mayo. Chop the parsley.

Rinse the oysters several times, then let sit in saltwater (water with salt added :-) ) until later.

Next we put the water and the sake into a pan and bring to a boil. This will evaporate some of the alcohol off the sake/wine. In the photo above I'll admit the water isn't quite boiling. Maybe it's at, or just beyond, the nucleate boiling stage.

 Once full boiling occurs add the oysters and return to a boil. Cook for about 3 minutes. They will plump up nicely.

 I prepared a baking sheet lined with tinfoil. Butter the tinfoil and leave some extra butter to melt when it goes into the oven.
Take the oysters out of the boiling water and pat them dry with a napkin. Place onto the foil lined pan. Then, using a spoon, spatula, or even your hands, put the garlic mayo mix onto each oyster. Be generous. 

Next I spread the Parmesan bread crumb mix over the oysters. You may want to add a bit of cream and more butter to the bottom of the pan if desired and raise up the foil to contain. Because I didn't use too much butter (or any cream) I didn't have as much juice as I wanted after cooking.

 Bake in the oven for about 5 minutes and then turn on the broiler. The pan should be about 5 inches or more away from the broiler element. Watch them carefully and remove when the cheese is golden brown. Add some pepper if desired.

Sprinkle on the parsley. Put one or two oysters on top of a piece of bread/toast and enjoy. This turned out really well. If you don't want to use wine or sake, you could use vegetable or chicken broth instead in the pan cooking phase. If you don't want to bother making them at all, then head on out to Hotaru!