If you're going to perfect one steak sauce, in our opinion it's got to be a Béarnaise. It's a classic French sauce, and is great with both meat and fish. The same technique is used to make a number of other delicious sauces with a Hollandaise base, so is well worth learning.
Recipe for Béarnaise
1 1/2 tbsp white wine vinegar
2 tbsp shallot, finely chopped
2 1/2 tbsp tarragon, chopped
3 peppercorns cracked
2 egg yolks
1 block of butter (250g), freshly clarified and luke warm.
Combine the vinegar, shallot, 2/3 of the tarragon and the peppercorns with 2 tbsp cold water, in a small saucepan. Reduce by half.
Let this cool, then add the egg yolks. Add 2 tbsp cold water, then place on a low heat.
Whisking constantly, pour in the butter slowly and bit by bit.
When the sauce has thickened, sieve out the shallot, peppercorns and tarragon, and season. A little lemon juice will make it more tart, if you prefer it that way.
Add the remaining tarragon and serve.