Heat oven to 425°F.
After dicing all the vegetables, steam everything but the shallots, garlic, and celery for 8-10 minutes until tender. Meanwhile, in a skillet heat the olive oil until shimmering and sautee the garlic and shallots until fragrant and translucent. Add the celery and cook until tender. Toss with the steamed veggies in a bowl and season lightly with salt and pepper.
Make your gravy. Melt butter in your dutch oven, and then whisk in the cup of flour to form a paste and cook, being careful not to brown, for about 3-4 minutes until it smells like pie crust. Slowly whisk in the four cups of stock in about four additions. Mixture will be thick. Add in the cheese, nutmeg, cayenne, salt, fennel pollen, sugar, and lemon juice and whisk to melt the cheese completely. Simmer mixture while whisking until very thick if not already very thick. Remove from heat.
Stir vegetables into the cheese gravy in your dutch oven. Taste and adjust seasoning if desired. Set aside, stirring occasionally to prevent a skin from forming, and make your topping.
In a mixing bowl mix flour, salt, baking powder, rosemary, thyme and cheese thoroughly to combine. Cut in the butter with your fingers or a pastry cutter until no pieces larger than a pea remain. Using a fork, stir in the buttermilk to just combine.
Dollop the biscuit dough on top to cover the filling; it needn’t be perfect. Bake at 425°F for
about 15-20 minutes, until golden brown, bubbling, and the topping is cooked through. Allow to cool slightly & serve hot. Garnish with fresh herbs if desired. I like parsley & celery leaf.