1. Cook peas in a large pot of boiling salted water 8 to 10 minutes or until just tender. Drain, rinse until cooled completely, and drain again.
2. Combine vinegar and next 3 ingredients in a small bowl. Add olive oil in a thin, steady stream, whisking constantly. Add sea salt and pepper; stir in jalapeño. Drizzle half of vinaigrette over peas, and toss to coat.
3. Arrange tomato slices on a platter or individual plates. Spoon peas over tomato, and serve with remaining vinaigrette. Sprinkle with basil, goat cheese, and additional salt and pepper, if desired.