First, prep the mushrooms. Wipe clean with a damp paper towel, then stem and quarter them.
Preheat oven to 375 degrees.
Heat oil in medium nonstick skillet over medium-high heat.
Add mushrooms, season lightly with salt and pepper, and sauté for 8-10 minutes until they lose their moisture and brown lightly. Remove from pan.
Add cream, mustard, and herbs to the hot pan, and cook gently for 3-4 minutes over medium heat, until sauce has thickened slightly.
Add chicken and mushrooms to the sauce, and season with salt and pepper to taste.
Put ⅔ cup of filling onto one side of each crêpe, then fold over the empty side, and fold again.
Arrange the filled crêpes on a baking dish and bake for 5-10 minutes to heat throughout. (You can also microwave the crêpes at this point to save time.)
Garnish with more chopped chives, if desired.
Notes
Serve with a green salad for a light lunch or dinner! Note: I listed the servings as 2-4, because it depends whether you will serve 1 crêpe per person, with a side, or 2 per person.