Promise.resolve().then(function() {
  console.log('starting');
  return 123;
}).then(function(val) {
  console.log(val);
  return val + 1;
}).then(function(val) {
  console.log('starting second step...');
  return new Promise(function(resolve) {
    setTimeout(function() {
      console.log('finished second step');
      resolve(val + 1);
    }, 500);
  });
}).then(function() {
  console.log('done');
});

// starting
// 123
// starting second step...
// finished second step
// done