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A heaped, bubbling individual zucchini gratin in a white ramekin, golden panko-parmesan crust over tender zucchini in a creamy sauce.
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Zucchini Gratin

Adapted from Ina Garten's Zucchini Gratin. Serves 4 in individual ramekins, or one 12-inch skillet.

Ingredients

  • 1 large yellow onion halved and sliced (about ½ lb)
  • 3 large zucchini large, not huge, not woody, sliced to about ⅛" (thickest mandoline setting)
  • 1-2 cloves garlic minced or pressed (go easy; this dish over-garlics fast)
  • 2 tbsp olive oil
  • 3 tbsp flour
  • 1-2 tsp kosher salt to taste
  • 1 tsp smoked paprika
  • 1 tsp mustard powder
  • 1-2 bay leaves
  • 1 cup warm milk 2% is fine; I used whole because that's what I have

For the topping

  • 3 tbsp butter I used salted; you do you, melted
  • ¾ cup panko or breadcrumbs
  • ¼ to ⅓ cup grated parm please don't use the green can; get the real stuff from the deli

Instructions

  • Preheat. Get the oven to 400°F.
  • Cook the vegetables. Heat the olive oil in a large pan (I used my 12-inch cast iron) over medium-high heat. Add the onions, and right when they start to turn translucent, add the garlic and zucchini. Cover and cook about 5 minutes, until the zucchini starts to darken, then uncover and cook a further 5 to 10 minutes to let some of the moisture evaporate.
    1 large yellow onion, 1-2 cloves garlic, 2 tbsp olive oil, 3 large zucchini
  • Make the roux base. Meanwhile, whisk the flour and spices together, and warm your milk (90 seconds in the microwave worked perfectly for me).
    3 tbsp flour, 1-2 tsp kosher salt, 1 tsp smoked paprika, 1 tsp mustard powder, 1-2 bay leaves
  • Build the sauce. Sprinkle the flour-and-spice mixture evenly over the cooking zucchini and onions and stir well. Add the milk and keep stirring and scraping, making sure all the zucchini is evenly coated. Reduce the heat to low and let it thicken.
    1 cup warm milk
  • Fill. Spoon into individual ramekins (heaped, please), or leave the whole mixture in the pan and bake it right in the skillet if it's oven-safe.
  • Top. Mix the panko, parm, and melted butter, and layer it over the top of the zucchini.
    3 tbsp butter, ¾ cup panko or breadcrumbs, ¼ to ⅓ cup grated parm
  • Bake. 15 to 25 minutes (less for the ramekins, more for the full skillet), until the crumb topping is golden brown and the filling is bubbling up around the edges.
  • Rest. Cool for 10 minutes before serving. I know it's tempting to dive right in; trust me, wait the 10. The sauce thickens as it cools, which means you get that lovely clean cross-section, and you (or your guests) won't take a bite of molten sauce and sear the roof of your mouth. Ten minutes. The anticipation is worth it.

Notes

  • Heap them: if you're using individual ramekins, mound the filling generously. Flat and level is fine; heaped and bubbling over is the whole point. (Three zucchini, not two, is what fills all four properly.)
  • Garlic, but gently: this dish does want garlic (Ina's has none), but it over-garlics in a hurry. One or two cloves, not a whole head.
  • The parm matters: deli parm, grated fresh, is a completely different food than the shelf-stable green-can stuff. This is the place to spend the extra dollar.
  • Don't waste the topping: any leftover panko-parm mixture toasts up beautifully in a spare ramekin and lives happily on the next day's salad.
  • Make it a skillet: short on ramekins (or patience)? Bake the whole thing in the cast iron and scoop it family-style.
  • The rest isn't optional: ten minutes out of the oven, every time. It sets the sauce and saves your mouth.