Yellow Squash Kale and Ham Strata with Ajvar Horseradish Cream

As casseroles come into season yet summer veggies like squash still linger, here's a comforting casserole with the convenience of no-boil lasagna.  I always have a bit of ham saved in the freezer for dishes like this for a quick preparation when comfort is needed.
Ajvar Horseradish cream sauce:
2 Tbsp butter plus 2 Tbsp canola oil
1/4 cup flour
2 to 2-1/2 cups milk
2 Tbsp Ajvar
1 Tbsp horseradish

1 large yellow squash, sliced
2.5 oz fresh baby kale
1/3 lb ham, cubed
1/2 lb Jarlesburg or Swiss cheese, grated
9x13-inch worth of no-boil lasagna sheet
1 doz fresh basil leaves

Heat oven to 375. Now prepare the Ajvar horseradish cream sauce. Melt the butter in the oil in a medium saucepan. Tip in the flour and whisk for about 3-5 minutes, until the flour is bubbly and the aroma becomes just nutty. Add 2 cups of the milk, the ajar and the horseradish. Continue whisking as the mixture comes to a gentle boil. Adjust the thickness with any extra milk as needed. Season with salt and pepper to taste, and remove from heat when nicely thickened.

Pour about one third of the sauce onto the bottom of an oiled 9x13-inch casserole dish. Lay half the squash slices on top of the sauce.

Sprinkle with half the grated cheese. Top with the kale, and pour on another third of the sauce. Then lay the remaining squash slices and half the ham cubes on top.

Lay the lasagna sheets over all and pour the remaining sauce over the lasagna. Sprinkle with the second half of the ham cubes, the remaining grated cheese, and distribute the basil laves about.

Bake covered for about 20 minutes, and then uncovered for about 20-30 minutes, until brown and bubbly.

Serves 4.