Step 1

1 Preheat oven to 350 degrees

Step 2

2 Line a baking sheet with aluminum foil

Step 3

3 Scrub potatoes under cold water, then cover lightly with a teaspoon or two of oil using your hands or a pastry brush

Step 4

4 Place potatoes on the baking sheet and prick the skin 4 or 5 times with a fork to let out the steam as they cook

Step 5

5 Bake (middle rack) for 50 to 60 minutes, until the insides are very soft when pricked with a fork

Step 6

6 Alternately, to cut the baking time, cook the oiled potatoes in a microwave on high for 5 minutes before baking in the oven for about 30 minutes, until soft

Step 7

7 Once the potatoes are out of the oven, cut in half the long way and open them to cool faster

Step 8

8 While the potatoes cook, clean and prepare the leeks

Step 9

9 Cut off the dark green tops and save for making stock

Step 10

10 (They can be washed and stored in the freezer until ready to use

Step 11

11 ) Cut off the roots and discard

Step 12

12 Pull off a couple of layers of the tough part of the white and any damaged parts

Step 13

13 Split the white of each leek lengthwise, then cut across into half-inch pieces

Step 14

14 You will have 8 to 9 cups of leek pieces

Step 15

15 Place the leeks in colander or strainer that fits into a large bowl (or pot) and wash under cold water

Step 16

16 Set the colander into the bowl and fill with cold water

Step 17

17 Let soak for a few minutes, then swish the leeks around to dislodge any grit

Step 18

18 Give the dirt time to fall to the bottom, then lift out the colander or strainer

Step 19

19 Toss and mix the leeks, checking for remaining grit

Step 20

20 As needed, rinse the bowl and repeat the washing process

Step 21

21 Alternatively, place the leek pieces in a large bowl and fill with cold water

Step 22

22 Let sit for a few minutes, then swish the leeks with your hands

Step 23

23 Wait a few moments for any grit to fall to the bottom, then scoop out the leeks with a slotted spoon, disturbing the water in the bowl as little as possible

Step 24

24 Set the leek pieces aside, rinse the bowl and repeat washing the leeks as needed

Step 25

25 Set a steamer into a pot with a few inches of water in the bottom and bring to a boil over high heat

Step 26

26 Place the clean leek pieces in the steamer, cover the pot, reduce the heat to medium and cook for 15 to 20 minutes, until very tender

Step 27

27 Transfer the cooked leeks to a colander or strainer and force out any liquid with the back of a spoon

Step 28

28 Scoop out the insides of the cooled potatoes, leaving a thin layer next to the skin

Step 29

29 The yield is about 4 cups

Step 30

30 Mash together the leeks and potatoes, breaking up any large lumps

Step 31

31 Add the grated carrot, beaten eggs, salt, pepper and the cheese, if using

Step 32

32 Stir until well incorporated

Step 33

33 Reheat the oven to 350 degrees

Step 34

34 Use 2 tablespoons of the oil to grease a 9-by-13-inch baking dish

Step 35

35 Place in the oven for 3 to 4 minutes, or until well heated, then remove it just long enough to spread the leek-potato mixture in the dish in an even layer

Step 36

36 (When the pan is really hot, the mixture should sizzle as it hits the oil

Step 37

37 ) The heated baking dish and its oil will help create a crust on the bottom and sides of the casserole

Step 38

38 Gently brush the top of the leek-potato mixture with the remaining oil

Step 39

39 Bake (middle rack) for 30 to 35 minutes, until the mixture is firm and golden brown around the edges

Step 40

40 Serve right away, or cool completely before storing