Peel the shallot and cut into fine cubes. Cut off the ends of the beans and blanch them in boiling salted water for 4 min. Add the peas and cook for another 1 min. Then drain and rinse in ice water.
Mix all the ingredients for the dressing and add the diced shallots.
Arrange the beans and peas on a large plate. Top with feta cheese and currants and garnish with mint.