1 large head cauliflower, trimmed and cut into florets
2 large leeks, white and light green parts only, cut into 1-inch-thick rounds
2 tbsp coconut oil, plus additional for greasing baking dish
1/4 cup coconut flour
1 1/2 cups unsweetened plain almond milk
1/4 tsp paprika
1/4 tsp ground nutmeg
Sea salt and fresh ground black pepper, to taste
1 1/4cups grated Swiss or Gruyère cheese, divided
8 oz thinly sliced smoked salmon
1/4 cup grated Parmesan cheese
1/4 cup sliced almonds
4 tsp chopped fresh chives or flat-leaf parsley leaves
Preheat oven to 425°F. In a large pot of boiling salted water, cook cauliflower for 3 minutes. Add leeks and cook until vegetables are tender, about 2 minutes; drain well. Transfer to a large bowl.
In a medium saucepan, melt oil on medium. Add flour and cook, whisking constantly, for 1 minute. Stir in milk and bring to a simmer, whisking often. Whisk in paprika, nutmeg, salt and pepper. Remove from heat and whisk in 1 cup Swiss cheese until blended. Pour sauce over cauliflower mixture and add salmon, stirring to combine. Lightly grease a 9 x 13-inch baking dish; scrape mixture into dish. Sprinkle with Parmesan and remaining 1/4 cup Swiss cheese. Top with almonds.
Bake until cheese is bubbly and nuts are golden, about 20 minutes. Sprinkle with chives.
Normally, gratins are layered horizontally so that the sliced vegetables lie flat in the dish. This recipe literally turns that on its side — the potatoes and artichokes are standing on their edges, so you get lots of crispy bits on top and a really fancy look that’s impressive on your holiday table.