A compound sentence joins two or more independent clauses with a coordinator such as and, for, or, but, or a semicolon. An independent clause is a sentence that can stand alone as a sentence as it represents a complete thought. In the case of the sentence above, the independent clauses that make up the compound sentence have been brought together by the coordinator "or".
The first choice (Using a sharp knife, cut each piece of bread diagonally into two equal pieces) It gives the reader a clear and detailed visual of how he is making the food Hope this helps!!