From-scratch green bean casserole

Chop the ends off the green beans and cut them roughly one inch long. Bring a pot of water to a boil with a large four-finger pinch of salt and have an ice bowl ready.

Blanch the beans two minutes, then straight into the ice water for about five minutes. This stops enzyme reactions and locks in the colour, flavour and texture.

Strain, spread on a cookie sheet evenly spaced so they do not stick, and freeze at least an hour before bagging.

Preheat the oven to 325F.

Cut the vegetables very thin with a knife or mandolin, avoiding too many sweet ones.

Optionally break up a sheet of kombu for umami, add about 30 g of tomato paste and a drizzle of olive oil and mix roughly.

Roast about two hours, tossing every 30 minutes, until browned and mostly dehydrated so the flavour concentrates.

Add the browned vegetables to a stock pot with 2.5 litres of water and return it to the oven for 45 minutes to leach the flavour out.

Transfer the stock off, then strain it back into the pot so only liquid remains.

Mark the level with a wooden spoon and reduce over medium heat, stirring occasionally, by about half or a little more.

Mix the salt, MSG and pectin, then slake them with a couple of spoonfuls of the hot liquid into a paste so they cannot clump.

Transfer to a smaller pot and add the dried porcini for the last 10 minutes.

Whisk the paste in until completely dissolved, taste and adjust the salt, and add more pectin or gelatin for more body.

Pour the demi-glace into ice cube trays to store.

Set a wok over medium-high with an inch or two of peanut oil and bring it to 325F.

Thinly slice one onion pole to pole, blot on a paper towel to take off excess moisture, then toss with about 50 g of cornstarch.

Fry the onions in two batches, moving constantly, until just golden brown; burnt onions turn bitter.

Drain on a wire rack over a baking sheet and mix in a pinch of salt. They crisp as they dry.

Freeze the whole sheet tray an hour, then bag; they crisp back up straight from frozen in the oven.

Preheat the oven to 400F, set a cast iron over medium low, melt a tablespoon of butter and cook about 80 g of mushrooms with a pinch of salt and 20 cranks of pepper until browned and dry.

Add the minced garlic, the second tablespoon of butter and about 25 g of flour and cook, stirring, about one minute.

Add a splash of wine and cook it off, then the 250 g of demi-glace; simmer and stir about two minutes until it thickens.

Add 400 g of half and half, return to a simmer and reduce, stirring, at least 10 minutes until thickened.

Stir in the frozen blanched beans and a handful or two of fried onions and bring back up to heat for two to three minutes.

Transfer to a baking dish, cover the top with as many fried onions as you want, and bake 10 to 15 minutes until the sauce bubbles at the edges and the onions crisp.