This is my retrofitted Black and Decker toaster oven for reflow soldering. To reduce the temperature gradient, the unit is insulated with 1″ ceramic blanket, Reflect-a-Gold tape, door sealant, and Boom Mat.
The controller is the popular ControlLeo2. A fan is used to improve the cooling speed. A temperature sensor and independent top and bottom heaters provide a consistent and accurate reflow profile.