In a large saute pan, melt butter over medium heat.
Once melted, stir in sliced mushrooms and cook until tender, about 10 minutes (more or less to taste).
In the last minute or two, stir in Boursin Monterey Jack & Spicy Pepper Cheese Dip.
Stir until melted. Season with salt and pepper and set aside.
Preheat oven to 425 degrees F.
Unroll the phyllo dough, and cut into three equal strips.
Place two sheets of the phyllo onto your work surface. Cover the stack of remaining sheets with a damp paper towel. They’ll dry out if you don't.
Brush the top sheet of phyllo with the smallest amount of melted butter. If you use too much, these will get greasy.
In one corner, place 1-2 tablespoons of filling.
Fold phyllo dough over the filling to make a triangle.
Continue folding back and forth in a triangle shape.*
Gently press to make sure the filling is sealed.
Pace on an ungreased baking sheet, and spritz with the smallest amount of cooking spray. Again, if you use too much, these will end up greasy.
Repeat with remaining dough and filling.
Bake for 8 minutes, gently flipping halfway through.
After baking, if they’re a little greasy, just dap with a paper towel.
Serve and enjoy!