tried-and-true
Proven to work well because it has succeeded many times.
Tried-and-true describes methods, approaches, or things that have proven reliable through repeated use over time. When something is tried-and-true, people have tested it many times and know it works.
A tried-and-true recipe is one your grandmother has made successfully for decades. A tried-and-true study method is one that's helped countless students learn effectively. When you use a tried-and-true approach, you're choosing something with a track record of success rather than experimenting with something new and uncertain.
The phrase suggests both testing (tried) and reliability (true). A tried-and-true fishing spot is one where people have caught fish many times before. A tried-and-true way to make friends might be showing genuine interest in what others care about, an approach that's worked for generations.
Sometimes people prefer tried-and-true methods because they want dependable results. Other times, they experiment with new approaches because innovation requires trying things that aren't yet proven. A tried-and-true technique won't surprise you, but it probably won't disappoint you, either. When the stakes are high and you need something that works, reaching for a tried-and-true solution makes good sense.