1. Place a large pot of water on high heat and bring to boil. In the meantime, heat the olive oil and garlic cloves in a small pan over medium heat until the garlic begins to sizzle, then reduce heat to low and cook very gently until the garlic begins to soften and take on colour, about 3 minutes. Remove from heat and set aside – it will continue to sizzle and cook for another minute or two.

2. When the water has come to a boil, add the kale leaves and add ¼ teaspoon salt. Cook for about 5 minutes until the kale is tender, then use tongs to transfer to a blender, reserving the cooking water. Add the garlic (including the oil) and about 2 tablespoons of the kale cooking liquid, then blend on high speed until it's a thick purée – add a tablespoon of water if not blending smoothly. Transfer purée to a small bowl, stir in ¼ teaspoon pepper, and set aside to cool (can be made up to 2 days ahead and refrigerated).

3. Melt butter in a medium saucepan over moderate heat until foam subsides, then add flour. Cook for about 2 minutes, whisking continually, then add the milk in a slow stream. Whisk until the sauce thickens, about 5 minutes. Add the cheeses, nutmeg, ¾ teaspoon salt and ¼ teaspoon pepper and whisk to combine. Transfer to a large bowl and allow to cool for 10 minutes before beating in the egg yolks and kale purée.

4. Preheat the oven to 210C (190C fan-forced). Using upward strokes, generously brush the inside of a soufflé or casserole dish (about 1.5-litre capacity) with the extra softened butter. Combine the breadcrumbs with the extra parmesan cheese, then sprinkle in the dish to coat evenly. Tap away any excess crumbs and place in the fridge.

5. Place egg whites in the bowl of an electric mixer fitted with the whisk attachment, add a pinch of salt and whisk until the mixture is shiny and holds stiff peaks. Fold about a third into the kale mixture to lighten, then fold in remainder gently but thoroughly – blending together without deflating the egg white. Gently spoon the mixture into the prepared dish and place on a baking tray, then into the oven. Bake on the middle shelf for 35-40 minutes, or until puffed, golden brown and just set. Serve immediately.

Tip: Don't worry about the dish you make it in, or the "rise". Keep it real and make it in a casserole dish – it will still taste great.