Prepare the Hash Browns according to the instructions on the packaging.
Chop the shallot. Reduce the tarragon vinegar with the shallot by half. Melt the butter in a saucepan over low heat, without colouring. Remove the melted butter from the heat.
Heat the olive oil in a frying pan. Fry the bacon slices for 4-5 minutes until crispy. Place them on a plate.
Let the spinach shrink in the hot bacon fat while stirring and the moisture evaporate. Season with salt and pepper.
Put the yolks with the leaves of the sprig of tarragon in the measuring cup. Pour in the reduced vinegar through a sieve. Slowly pour in the melted butter and beat with the hand blender until creamy. Season the béarnaise sauce with salt and pepper.
Place the Hash Browns on a platter. Divide the spinach and bacon on top. Garnish with the béarnaise sauce and grind over black pepper to taste.