Served with simple green salad.
Combine all pastry ingredients in a food processor (mix flour and butter, then add water gradually while mixing).
Gather into a ball, cover with plastic wrap and chill 1 hour.
Saute onion until shiny in the butter.
Stir in salmon, chives, garlic, and basil. Cool.
Preheat the oven to 400F.
Roll out the dough to fit a 10" tart pan. Prick with a fork.
Arrange the salmon mixture in the pre-baked tart shell.
Whisk eggs with milk and cream, season with pepper and pour in the tart shell.
Bake about 30 minutes at 325F, until puffed and golden.
Make the salad: slice the cucumber and toss it with the spring mix, olive oil, balsamic vinegar, salt and pepper.