1.Combine wine and juice in small saucepan; bring to a boil. Boil, without stirring, until reduced by two-thirds. Add cream; return to a boil then reduce heat. Whisk in cold butter, piece by piece, whisking between additions, until sauce is smooth and thickened slightly. Do not add butter too quickly, otherwise mixture will separate. Do not allow sauce to boil when adding butter.
2.Optional: to make toasted sesame and chilli beurre blanc, after butter has been added, stir in 2 teaspoons toasted sesame seeds and 1 finely chopped fresh small red thai chilli.
3.Optional: to make roast garlic and lemon beurre blanc, roast 8 garlic cloves in oven at 200°C (180°C fan-forced) about 15 minutes or until garlic softens. When cool enough to handle, peel; chop garlic finely. Stir garlic and 2 teaspoons finely grated lemon rind into beurre blanc after butter has been added.