How do I cook consistently under pressure?

You have the techniques now, but holding them steady under pressure still beats you, and that is the hardest jump in the kitchen. Knowing how to do something calmly and doing it well when the tickets pile up and the heat is on are two very different skills. You have the first. The second is built, not born. Pressure does not erase your technique; it just crowds out the attention the technique needs. When you rush, you skip the small checks that make each dish right. The cooks who stay sharp under fire are not calmer by nature. They have drilled the moves so deeply that pressure cannot shake them loose. Pick the one technique that falls apart first when you are slammed and drill it until it is automatic, when things are quiet. Then it will hold when they are not. Consistency under pressure is just practice made deep enough to survive chaos. Build one steady move at a time, and the storm stops rattling you.