A greenhouse was this year's goal and aquaculture (done)l. If you live in a region of the world with harsh winters, then a greenhouse will be essential for food self-sufficiency. Obviously, a greenhouse alone is not a strategy for full food production unless it is a large facility. Typically it can be viewed as a compliment to other gardening methods.
Indoor growing is typically done with grow lights and hydroponics. Some people have sun-rooms in their homes which can basically act as a fancier greenhouse.
Indoor hydroponics. This method of growing is certainly not the cheapest way to produce food, yet it is a steadfast method especially where weather and other elements can hinder food self-sufficiency. Indoor hydroponics requires grow lights such as LEDs, CFLs, or HPSs, along with tubing, drainage, fertilizer and ventilation. However, even a small space can produce fantastic yields for leafy vegetables, herbs, tomatoes, sprouts, and much more. To make this method fully off the grid find the most energy efficient grow lights possible and think about getting a solar generator to offset the electric costs.