Heat oven to 350 degrees. Mist a 13- by 9-inch baking dish with nonstick spray and set aside.
Microwave beet greens in a covered, vented microwave-safe container for about 3 minutes, stopping to stir and turn greens once. Remove from oven and set aside.
Heat olive oil in a 12-inch skillet and sauté onion for about 5 minutes, until tender, stirring frequently. Add garlic during the last minute of cooking so it won’t burn. Add corn, chile and drained greens, stirring to combine well and cooking for another 2-3 minutes. Turn off heat.
In a saucepan, melt butter and add flour, stirring and cooking over low heat to make a roux (a paste-like mixture). Cook and stir for 2 or so minutes (so the flour won’t have a raw taste), and the mixture is beige or just pale golden. Slowly add milk, stirring constantly, and turn up heat to medium. Add salt, cumin and pepper. Use a whisk to whisk the milk mixture smooth, and cook it until it boils, which might take 5 or so minutes. Once it boils, boil the mixture, whisking frequently, for 1-2 minutes, until it thickens.
Stir the thickened milk mixture into the greens/corn/chili mixture. Stir in the cilantro. Quickly stir the beaten eggs into the greens mixture.
Layer half the tortilla strips on the bottom of the prepared dish. Spoon half of the greens mixture on top. Layer the rest of the tortilla strips and top with the rest of the greens mixture. Top with cheese and bake for 45 minutes or until nicely browned on top.
Remove from oven, allow to cool for 5 minutes, and cut into rectangles to serve.
The green in Green Corn Tamales means the corn is fresh rather than dried. It doesn't refer to the color of the corn, although fresh husks are green, of course.
Traditional tamales are made by a group of people who create a party out of their preparation – think of it as a prelude to the party at which they will be eaten. It’s a good thing that many hands make quick work, because these stuffed, steamed packages wrapped in corn husks can be quite labor intensive.
So this version of the classic green corn tamale – enriched with additional greens – is far less work than a traditional tamale, with all the flavor intact.