Scalloped Ham Potatoes and Leeks with gruyere

3 cups leeks , washed very well and then thinly sliced (about 6 large, white and pale green parts only) 1/2 cup unsalted butter 3 1/2 cups whole milk 6[...]

1/4 cup butter 2 lbs sliced leeks 1 tablespoon butter 2 cups whipping cream 3 garlic cloves 4 lbs yukon gold potatoes 2 cups grated white cheddar cheese 1/2[...]