In a medium skillet over medium-high heat, melt 1 tablespoon butter. Stir in flour and cook about 1 minute. Whisk in stock, dill or tarragon and Dijon, and cook until well thickened and season with salt and pepper.
Heat a large skillet over medium heat with 1/2 tablespoon butter. While the skillet is heating up, mix together the pancake mix, milk and eggs in a large bowl then fold in the chicken, peas, carrots, celery, scallion and zucchini until incorporated.
Pour mix into the skillet, making the pancakes as large as you want (just make sure theres a little bit of everything in each). Cook until golden brown on each side, about 2 minutes per side, and continue with the rest of the batter -- add a little more butter to the pan before each batch. Place cooked pancakes on a plate and keep warm in a 250F oven with foil on top.
When all the pancakes are done, stack 3 per person on a plate topped with the herb-Dijon gravy as the syrup.