Heat a medium skillet (frying pan) on medium high for 1 to 2 minutes.

Add the leek and cook, stirring, until they are tender, 2 to 3 minutes.

Add the mushrooms, garlic, thyme and season with 1 teaspoon salt and a big pinch of black pepper.

Cook until the mushrooms have released their moisture and are dry, 6 to 7 minutes.

Transfer the mushrooms to a bowl and add the cottage cheese and walnuts.

Taste and season with salt and pepper as needed.

Preheat oven to 350˚F / 180˚C.

Prepare a baking dish - I used a 9 x 13inch baking pan.

Unroll your filo pastry, count out 12 sheets, and using your baking dish/pan as a guide, use a pair of scissors to cut the sheets to size so they will fit into your pan.

Brush the bottom of the pan with melted butter and then place 3 sheets of filo pastry on top, brush the filo with butter, and then place another 3 sheets of filo on top and brush with butter.

Top with all of the mushroom mixture, using a spoon to smooth it out into a thin layer.

Next top with another 3 sheets of filo, brush with butter, and finish with the final 3 sheets of filo, brushing it with butter.

Using a sharp knife, cut through the top of the filo, extending into the mushrooms, to make squares or a diamond pattern.

It helps to use your non-dominant hand to hold the pastry down while you cut.

Add the maple syrup to the remaining butter and stir.

Pour this over the top and scatter with sesame seeds.

Bake until the top is golden and crispy, 45 to 50 minutes.

Allow to sit for 5 to 10 minutes before slicing and serving.