C# - Using A User Control In A Base Page Class

I have a base page class that inherits from Page. We'll call it SpiffyPage. I also have a user control called SpiffyControl. I then have an aspx page, ViewSpiffyStuff.aspx, that inherits from SpiffyPage. On page load, the SpiffyPage class is supposed to inject a SpiffyControl into the aspx page. The problem is that SpiffyControl is a user control, and to instantiate that in the code behind one has to access the ASP namespace, sort of like: ASP.controls_spiffycontrol_aspx MyControl;

But SpiffyPage isn't an aspx page, it's just a base page, and as such I can't access the ASP namespace, and I therefore can't instantiate a SpiffyControl in order to inject it. How can I achieve my goal?

Edit: One important point is that I must have a reference to the actual control type so I can assign values to certain custom Properties. That's why a function like LoadControl, which returns type Control, won't work in this case.