May's New and Improved Gratin Instructions

This recipe is the result of several of several experiments that are still on-going. I will update this as I go along. 

Ingredients
Potatoes, sliced thinly -- weighed after peeling and slicing
salt

Place sliced potatoes in a pot. Cover with water, add salt, and bring to a boil. Turn off the heat, and drain potatoes right away, reserving the water.

Make white sauce as per your normal recipe, starting with the milk and then following up with the reserved potato water. 

Make gratin as per usual.

Notes: 

I used water only this time, as it was an experiment. If you usually make a 100% milk white sauce, you can use the milk portion of the recipe to cook the potatoes.

There will be starch in the water, and it will thicken up more than you think. Of course, the starchier the potato that you use, the thicker it will get. So you may want to reduce the amount of flour you use in the sauce.

Most recipes that have you boil the potatoes have you cook them for much longer, until the potatoes are almost cooked through. Even worse, they may have you cook them whole and then slice or cut them. I find that doing it that way makes it difficult to get the potatoes into the pan easily. The potatoes may be slightly sticky to handle this way, but they are almost as solid as raw.

This method also allows you to preserve more flavor, as the potato water goes back into the sauce.

It is important to drain the potatoes right away, especially if they were sliced thinly. Once the slices are cooked through, they are a pain to position in the gratin pan, and letting them sit in the water is potentially enough to cook them all the way.

I also find that there is much less slumping when cooking a gratin this way, so if you do not want a short gratin, this is an excellent way to do it.

Fennel and Potatoes in Cream

Adapted from Food52

Ingredients: 

1 fennel head
5 potatoes

black pepper
2tsp coarse salt
1 bay leaf
200g milk
200g cream

Chunk up the potatoes.

Cut off the fronds and other dark green bits of the fennel for another use. Quarter it, cut off the hard rooty bit, and pull it apart. Slice them into roughly the same dimensions as the potatoes.

Pour the rest of the ingredients into a pan, and warm up on low heat. Stir, then add the potatoes and the fennel.

If the milk does not submerge the vegetables completely, cover the pot. Keep an eye on it because milk has a tendency to bubble up and out of the pan and it is a terrible mess to clean up.

Cook for about twenty minutes, or until tender. Taste for salt.

At this point, you can drain the vegetables, reserving the milk liquid for another use. You can serve the vegetables at this point.

You can also portion them out onto gratin dishes and broil them until crispy. I recommend brushing a bit of oil over the top to help it crisp up faster.

Notes: 

You can swap out the fennel for leeks, if you like, or the potatoes for another root vegetable. Parsnip would probably work well.

For flavor, you can add a clove of garlic, garam masala, chilli flakes, amongst other things, to the milk. But if you use fennel, I actually suggest adding fennel seed instead, because I am afraid the garlic etc will over power the fennel.

Next time, I will probably not use cream. It is not necessary.

You can use the milk after that in a roux-based sauce. I plan to fry up some steak in butter, use that to make a roux and dump in the milk after that.

Savory Mash Potatoes

Ingredients: 
650g cubed potatoes -- after washing, peeling and cutting
200g chicken stock
100g butter
1 clove garlic

Sous vide at 80C for 2 hours and 15 minutes.

Future Notes: 
Add salt at the beginning of cooking, not half way through because you forgot.
Higher temperature needed. Chef Steps has it at 90C for about half an hour.