Sausages with Parsnip Mash

From the garden

• 2½ lb parsnips, peeled and cut into 2-inch chunks · cut the woody core out of any thick roots
• 2 large yellow onions, halved and sliced thin
• 1 tbsp fresh sage, chopped

From the pantry

• 1½ lb smoked sausage or thick pork sausages, left whole
• 4 tbsp butter · divided
• ½ cup whole milk, warmed
• 2 tbsp all-purpose flour · for the gravy
• 2 cups chicken stock
• 1 tsp Worcestershire sauce
• 1 tsp Dijon mustard · stirred into the mash
• 1 tbsp olive oil
• salt · to taste
• black pepper

1. Cover the parsnips with cold salted water, bring to a boil, and simmer 15 to 18 minutes, until a chunk collapses against the side of the pot. Drain, return them to the dry pot, and let the steam escape.
2. Brown the sausages meanwhile in a heavy skillet with the olive oil over medium heat, turning them until colored all over, about 10 minutes. Move them to a plate and leave every bit of fat in the pan.
3. Cook the onions in that fat over medium-low with a pinch of salt, scraping up the browned bits, 15 to 18 minutes, until collapsed and genuinely sweet. Stir in the sage for the last minute.
4. Sprinkle the flour over the onions and cook it 1 minute, then pour in the stock in stages, whisking after each. Add the Worcestershire and simmer 5 minutes until the gravy coats a spoon, then return the sausages to warm through.
5. Mash the parsnips over low heat with 3 tablespoons of the butter, the warm milk, and the mustard until smooth. They go silkier than potato and will not turn gluey, so mash as hard as you like. Season well with salt and pepper.
6. Spoon the mash onto warm plates, lay the sausages over it, and flood everything with onion gravy, dropping the last of the butter on top to melt in.