Learn Russian: Пирог горячий.

In Russian, the present tense of the verb "to be" is almost always left out. So, instead of saying "The pie is hot," you simply say Пирог горячий (literally: "Pie hot").

Why does the word for hot end in -ий (горячий)?

Adjectives must match the gender of the noun they describe. Because пирог (pie) ends in a consonant, it is a masculine noun. Therefore, the adjective takes a masculine ending, which is usually -ый or -ий.

Based on this lesson, how would I make пирог plural to say "pies"?

You would say пироги. Normally, masculine nouns ending in a hard consonant take -ы in the plural. However, because of the 7-letter spelling rule, you can never write ы after the letter г (or к, х, ж, ч, ш, щ). Instead, you must use -и.

Does the г at the end of пирог sound like a "k"?

Yes! In Russian, voiced consonants like г (g) become unvoiced and sound like their harder partner (in this case, "k") when they are at the very end of a word. So пирог is pronounced like "pee-ROK". If you make it plural (пироги), the г is no longer at the end, so it gets its normal "g" sound back.