In rough terms, the speed at which you can apply the brake pedal is related to your spring and damper rate. The stiffer the spring and damper the faster weight transfers so the quicker the front tyres load up and generate more traction allowing you to brake harder. The softer the spring and damper, the slower you need to apply the brake as the weight transfers forward more slowly taking longer to load the front tyres, which generates the traction to allow you to brake hard.
Unless you are driving a ‘downforce’ car, then just hit the pedal as quick and as hard as you can. The downforce is already pushing the tyre into the track generating traction and in anything with GT3 or higher levels of downforce its almost impossible to block the brake at speed as the downforce generates more traction than the brake can overcome.