// specimen 1
const KEY_VALUE = {
  'prop-key-1': 'some-prop-value-1',
  'prop-key-2': 'some-prop-value-2'
};

Object.keys(KEY_VALUE).forEach(key => {
  // do something with key and KEY_VALUE[key];
});

// specimen 2
interface KeyValue {
  key: string;
  value: string;
}

const KEY_VALUE: KeyValue[] = [
  {
    key: 'prop-key-1',
    value: 'some-prop-value-1',
  },
  {
    key: 'prop-key-2',
    value: 'some-prope-vale-2'
  }
];


KEY_VALUE.forEach(pair => {
  // do something with pair.key and pair.value
});