For the pork tenderloin with vegetables, first prepare the béchamel.
For the lemon béchamel, melt the butter in a saucepan, add the flour while stirring with a whisk and sweat until golden. Add the milk while stirring.
Add the bay leaf, season the sauce with salt and cook over a gentle heat for 20-25 minutes. Finally, finely grate 1 tsp lemon zest and stir in.
Pour the sauce through a fine sieve into a saucepan, stirring well, and season with salt.
For the pork tenderloins, pluck thyme and rosemary into short pieces. Wrap pork medallions with 1 bacon slice each, tie tightly with twine.
Tuck some thyme and rosemary between each meat and bacon. For the vegetables, clean the cauliflower and broccoli and divide into small florets. Clean and peel the carrots and cut them diagonally into 2-3 cm long pieces.
Peel the potatoes, cut them into pieces and bake them in the oven at 150°C until they are cooked. Cook cauliflower and broccoli one by one in boiling salted water for 5-6 minutes and drain well.
Melt 10 g butter in a large pot, sauté carrots in it over medium heat for 1-2 minutes, season with salt. Deglaze with mineral water and cook, covered, over moderate heat for another 4 minutes.
Melt 10 g butter in a coated pan and season with salt and pepper. Add remaining butter, carfion and broccoli to carrots.
Heat the oil in an ovenproof coated frying pan and brown the medallions in it.