HybridCache is the recommended caching approach for new .NET 10 projects, combining L1 in-memory speed with optional L2 Redis durability through a single GetOrCreateAsync API. Key features include built-in stampede protection (100 concurrent requests on a cold cache result in exactly 1 database query), tag-based invalidation via RemoveByTagAsync, and automatic L1/L2 coordination. L1 hits benchmark at ~0.05 microseconds — only 30ns slower than raw IMemoryCache but 24,000x faster than Redis IDistributedCache calls. The guide covers full setup in ASP.NET Core .NET 10, Redis as L2 backend configuration, migration from IDistributedCache, BenchmarkDotNet performance numbers, common pitfalls (L1/L2 expiration mismatch, serialization failures, overly broad tag invalidation), and a live stampede protection demo with log proof.