Boerek is a layered pastry made with phyllo dough and a filling. This recipe uses spinach and feta cheese, but there are a lot of recipes out there with other fillings. Some borek recipes have you roll up the filling into “cigars” and bake them on a cookie sheet. This one is made like a lasagne and then cut into servings. Maggie and I make the lasagne-type for a family dinner and the cigar-type for a buffet. You can eat these warm out of the oven or cold or reheated in the microwave or a toaster oven. (Re-heating in the microwave loses the crisp.)
IMPORTANT! The borek requires resting in the refrigerator for at least 2 hours before baking, so make sure there is room in the fridge before you start.

10 phyllo sheets, fresh (or thawed overnight if you bought frozen)

For the milk wash:
3 tbsp (45 ml) vegetable oil
1/2 cup (118 ml) milk
2 tbsp (30 ml) plain yogurt
1 egg
Salt and pepper to taste

For the filling:
1 lb (450g) fresh baby spinach (or 10 oz (280 g) frozen spinach)
1 tbsp (15 ml) olive oil
1 onion, diced
1 cup (150 g) feta cheese, crumbled
Salt and pepper to taste
2 tbsp (18 g) sesame seeds

For the egg wash:
2 egg yolks

Whisk the milk wash ingredients together and set aside
Sauté the onion in the olive oil for about 5 minutes or until they are soft
Add the spinach, salt and pepper.
Cover and cook until the fresh spinach reduces ( a lot!) or add the frozen spinach and heat it through.
Turn it off and let it sit for 15 minutes.
Put it in a mesh strainer to get all the liquid out.
Combine the spinach and the feta cheese in a bowl.
Line a baking sheet with parchment paper and lightly coat it with vegetable oil. (You can use spray oil)
Lay two sheets of phyllo on the baking sheet with 3 tbsp milk mixture on top. Spread the mixture evenly.
Lay two more sheets and repeat with the milk mixture.
Lay one sheet and spoon the spinach on top. Spread it out. Crumble the feta evenly over the filling and lay one sheet on top of the filling. Spread milk mixture.
Lay two sheets of phyllo and spread milk mixture.
Last two sheets of phyllo and spread milk mixture.
Beat the two egg yolks and spread this over the top of the boerek.
Cover with plastic wrap and put it in the refrigerator for at least 2 hours. It can be refrigerated overnight to bake the next day.

To bake:
Preheat oven to 350 F (190 C)
Spread the egg yolk wash over the top of the dough and sprinkle with sesame seeds.
Pre-cut the borek into serving sized pieces, either into squares, rectangles, or diamonds.
Bake for 30 – 35 minutes, until it is golden brown.