Make a marinade for the tender with all the ingredients except the roux and put
in a roasting bag along with the tender. Close well and let it marinate in the
overnight refrigerator.
Preheat the oven to 200 degrees and put the whole bag in the oven, inside a roast,
for about 40 minutes.
Remove the tender and reserve. Strain the sauce and reduce in a medium saucepan for 5 minutes in
medium heat.
Make a roux. Melt the butter, add the flour, keep stirring and cook for 1
minute. Add the sauce to the roux pot and stir well with a whisk to thicken.
Proce, adjust the salt and set aside. In a large pan, melt the butter and sauté the onion.
until golden. Lower the heat, add the bacon and sauté for 5 minutes. add the
garlic and wait for the aroma to exhale, add the chestnuts and stir for 5 minutes. add to
flour and stir until crispy, be careful with high heat and stir well so it doesn't burn
the background. Hit the salt.